I don't know how often you think about it, but technology (and the internets that connect it all together) is incredible. Devices are easier to use, software is better developed, and we're all more savvy. There's never been a better time to collaborate. Let's connect. Let's work together. Let's make something with the best tools on the market.
The free account is most likely all you'll need, with 2GB of storage and options to share files with other Dropbox users or send web links to those who aren't yet on Dropbox. The apps are well designed, the website is clean, the entire system rarely has issues. I keep a Dropbox shortcut on my sidebar and manage most of my work inside that folder (that is both local to my laptop and uploaded to the cloud). Then when I'm on the go, I can get those same files on my phone or tablet without the worry of having to sync. It's auto-magical.
Google Drive is similar to Dropbox, and is just a rebranded version of the Google Docs that you've likely used in the past. Just like Dropbox, there are now specific apps to download on your system (and your mobile devices), and it actually works very much the same way.
The fresh interface is a vast improvement over the old Google docs way of doing things, and the changes are most notable with spreadsheets. In fact, I think the Google Drive app on a smartphone (Android | iPhone) is currently the best way to work with spreadsheets in the mobile space. You likely won't need to adopt both a Dropbox and a Google Drive. Your preference for cloud storage will lean toward Google Drive if your workflow involves mostly sharing Office-like documents such as spreadsheets, presentation, and word documents.
It's the task manager just about everyone uses (except me**). It lets you make lists, write notes, and store photos, and with the premium version you can share and edit these files to collaborate with your team. There's been a recent update to Evernote that makes things easier to manage, with a crisper layout. Evernote also is well integrated with other apps and browser extensions so that wherever you are, an Evernote link is nearby.
**If you're curious, I prefer Wunderkit for collaborating on a task management level. I won't recommend it here because the dev team is withdrawing support for it to focus on Wunderlist 2 — which should be out later this year. Fingers crossed that it has the great features of Wunderkit built in from the start.
What's your favorite way to collaborate online?