While you can't prepare for everything, there are some tech tools worth having around--even for the smaller emergencies, like when the batteries on your wireless mouse finally stop working. If you're part of a technologically inclined household, it's worth making a kit in advance that contains the following 10 tools.
1. Torx Screwdriver Set
A set of Torx screwdrivers, or even tiny Philips head screwdrivers, is really handy to keep around if you ever need to take apart your computer--for instance, if something stops working or gets water damaged. You can pick up a set like this at Home Depot for about $6.50. This particular set is especially handy if you own an Apple laptop.
2. Recovery Disc For Your OS
Always keep a recovery disc of OS X or Windows around to restore your computer to its factory state in case a virus attacks your data, or things start malfunctioning. In most cases your computer came with one, so it's just a matter of remembering where you put it.
3. LED Flashlight
When the power goes out, an LED flashlight is a powerful light source to find your way around. It doesn't have to be the world's brightest LED flashlight (like the one pictured)--just a basic one will do. They're also handy when you're something goes wrong with your tech and you need to look in the back at the devices wiring.
4. Backup Batteries
Having backup batteries for your various devices is pretty much a no-brainer. Be sure to keep a full stock of AAs, AAAs, and 9-volt batteries for everything from wireless peripherals and TV remotes to your fire alarm.
5. Ethernet Cable
If you're like me, you never run an ethernet cable to any of your computers because you prefer going wireless. But, if your wireless router goes out, always have an ethernet cable lying around just in case you need to connect your computer directly to your modem.
6. Surge protector
A surge protector is a great way to create more sockets to plug in your devices, but it also does what you'd expect--protect your devices from electrical surges. Be sure to use one with your important electronics. They also make it easy to turn off multiple devices with one switch, to save power.
7. Thumb Drive
I usually transfer files wirelessly, but in a pinch it's good to have a thumb drive around in case you need to transfer an important document. The larger the capacity, the better.
8. Paperclip
Ever needed to reset a router or eject a sim card, and not had anything thin enough to push the button? With most devices, a paperclip will do the trick. Be sure to stash one in your emergency kit.
9. Backup Peripherals
It's always a good idea to have backups of the most basic peripherals, like your keyboard and mouse. You never know when you might spill a cup of coffee all over your keyboard, rendering your entire computer useless.Your backups don't have to be fancy--they just have to work.
10. Battery Backup
Battery backups aren't terribly cheap (this one from Office Depot will set you back $75.99), but they can be a lifesaver if you're using desktop computer. Plug your stationary devices into one, and it'll not only protect them from power surges, but in the event of a power outage it will also provide battery power for a certain amount of time. So, even if your power goes out, you can continue to use your internet connection and desktop computer for sometime.
What are the tools you most often reach for tech? Let us know in the comments!

Shaw's Original Fir...
I usually use an earring as the 'paperclip'... I work in I/T and I never have to worry about carrying it separately as it is always with me.
I would also include a somewhat up to date bootable clone of your system. It's a backup and an emergency usability solution all in one, and nothing will make the average user feel more like a badass.
1. Tool Kit - http://www.ifixit.com/Tools/Pro-Tech-Toolkit/IF145-072-1 --This kit has just about everything from tearing down your desktop PCs and Macs to removing screens from your iDevices. This is a good deal if you currently have ANY tools for such work.
2. Your OS of choice on CD/DVD as well as a bootable USB drive (I have a 16GB for each OS - Windows 7, OSX, and Ubuntu). The Mac Mini and all current Mac Books do not have optical drives, hell, my desktop PC was built without one (I didn't need it when I bought the parts).
3. A good flashlight, such as a Coast A20 or Surefire G2. Both are weather/water resistant and are small enough to roll into your kit.
4. If you can afford it, pick up rechargeable batteries for each of your devices, and pick up 4 more than the total devices you have, just in case you lose power or need to refresh them in the charger. AA, AAA, 9V, CR123, C, D cells all have a rechargeable offering, if you know where to look (hint: Amazon or your home improvement store).
5. I'm the opposite, ethernet everywhere! In my kit I keep 2 lengths (cat 6) with me: 6 feet and 24 feet, depending on what I'll be working on. Wifi is only used for my cellphone, laptop, and tablet (which I will be selling shortly). If you have a large home, wifi might be an easy way to go, but for me, wiring my apartment was dirt cheap and simple to do, I also paired a dual band wireless router for my Boxee Box and my portables.
6. Smart power strips, that's all I need to say.
7. Newegg has 64GB flash drives for $27.99 and up. Wouldn't hurt to get one for each member of the household.
8. Paper clips, lock pick kits, and small drivers in your kit can all do (generally) the same function. For resetting a router, a ball point pen does just fine. For a SIM card, I've never really had much issues (unless you are talking about an iDevice). If you do repairs for iDevices, I'd recommend a paperclip be included in your kit (or stash away the SIM tool that came with your iPhone/iPad), if not, don't worry as you should have plenty of other replacements in your kit.
9. Microsoft Desktop 400. I have this specifically for any issues/needs when working on systems to be repaired (like when someone brings you only the computer itself, no peripheral). It's only $18 online.
10. Battery backup is used for my NAS only. My desktops are on a surge protector and any documents I work on are done in Libre Office, which auto saves every minute or so, and has yet to fail me on recovering a document after a power outage.
11. Invest in a NAS. The "cloud" has me a little paranoid about my data security if I were to rely on their services (Google, Apple, Microsoft, Dropbox, etc). Not to mention that you can make your personal "cloud" as big as you want, mine is 12TB (along with a redundant 4TB hard drive for data integrity, for a total of 16TB, but only 12TB are directly usable). Synology makes a robust and easy to use system for setting up your backups, serving up media, and even acting as a torrent server (set and download), plus apps for browsing and using your NAS on the go for iOS and Android. Qnap is another good choice in NAS offerings, providing nearly the same functionality and support for mobile devices as well (and both have apps repositories for additional functionality). Qnap and Synology sell their NAS's without hard drives, so pick what you can afford, they offer 1 drive boxes for around $150 and offer bigger boxes (up to 24 drives) costing upwards of $10,000+.
12. Spare parts for your computers/devices. RAM, hard drives, a small monitor, and (sometimes) processors are laying around my tool drawer (in their boxes of course) for any issues I may run into down the road. These aren't for swapping into an aging system, these are to keep me up and running until I can perform a system wide upgrade (such as the Mac Mini I'm looking at buying, I'll keep a 4GB kit around for "issues" purposes, but it's not going to be a replacement for the 16GB I plan to toss in it). And depending on your phone, I'd buy an extra screen and glass (especially on the iPhone) on hand to keep me from having to buy a whole new phone. I am notorious for buying devices and keeping them running for much longer than necessary, simply because I hate throwing money away every two years for something new while my old stuff still functions and looks like it just came out of the box, but I also have to thank rom devs for keeping my phone (Galaxy Vibrant) relevant for this whole time (until the battery decided to commit suicide, taking the main board with it). I plan on keeping my Galaxy Nexus alive for as long as possible.
13. Keep learning new techniques and skills to work on your hardware more efficiently, safely, and cleanly. You don't want to dive into taking apart your iPhone because you thought that working on your lawn mower provided you with enough "experience" with taking things apart. Watch videos, read disassembly guides, and if you can, watch someone else who is skilled doing what it is you plan on doing.
*Note - If you still take your systems to Geek Squad, you deserve to throw away your money. They over charge and hardly do any actual work. Look up 'Agent Johnny Utah Best Buy' and see how they actually do their software repairs. As for hardware, you'll get shafted by higher priced components, ridiculous labor costs, and the 'Best Buy Tax'. I was a tech for them a few years back and can tell you that for what we were paid for, it was quite disproportionate for the work we actually did. I can go further into the joke that is Geek Squad if you want, but I have already eaten a lot of room in this thread.
@JAMESSICKSIX -- THANK YOU!!!!!!!!!
Paperclip: pulls out cd-dvd tray and resets service processor.