Spreading bills out on the coffee table will only work for so long. Eventually, you may need to find a spot in your living room for a proper desk. Here are some location options to get your gears turning and inspire you to fit a real desk into your living room.
In a Side Table
Group your office supplies into organizing boxes (as shown above) and stash them into a shelving unit by the sofa to use as a side table. Keep at least a little space on the table clear to work on.

In Part of a Bookcase
Use a bookcase unit with adjustable shleves to configure a small workspace that packs a punch with storage. For extra credit, hide your office away behind curtains or a panel on rails.

Behind the Sofa
Tuck a long, narrow table behind your sofa for a place to keep your laptop and sort through paperwork. A chair or stool that can tuck completely under the desk will maximize your available space.

Behind a Partition
Use a screen, shutters or a curtain to keep your desk hidden from the rest of your living area.

Under the Stairs
That awkward area underneath an open staircase is a great spot for a small workspace and a few shelves.

Inside an Armoire
Take a hutch or armoire and customize it to your workflow for a home office that you can shut down at the end of the day. Or, find a secretary desk that's already in perfect working order for your workspace.

Inside a Closet
A storage closet, linen closet or even a small coat closet can be turned into a workroom by finding a desk and shelves that fit the space. Leave closet doors on or off, depending on how much you want to be able to hide your office away.
(Images: 1. Better Homes and Gardens, 2. Martha Stewart Living, 3. Better Homes and Gardens, 4. My Home Ideas, 5. Steve & Nancy's Vintage Sunset-Inspired Home, 6. Real Simple, 7. Jason's Closet Office)

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I've always loved the idea of an office area beneath the steps. That was my vision for my new space, until I saw the armoire idea. Definitely thinking outside the box here!
Love the desk under the stairs! That space always seems to be wasted.
I want this office in my living room:
http://www.restorationhardware.com/catalog/product/product.jsp?productId=prod1870777&categoryId=cat1850025
I used a closet to hide a workspace in a bedroom for a while. My bedroom had a large closet, with 3 sliding panel doors. I devoted one third of the closet to a small desk area. If you have the closet space to spare, I recommend this option; it has the advantage of giving you the closet walls to work with.
This is great!!! I am a professional organizer and I already recommend some of these to my clients but got some new great ideas from here
I've also incorporated my home office into my bedroom using a mikael desk and besta furniture from Ikea. Aside from not wanting doors for my besta wardrobe I think it came out great as everything is consolidated to one side of the room while leaving enough room on the other side for my bed and other things.
http://www.flickr.com/photos/wattsbw2004/7074505671/
I enjoy using the dining room table as my office. I have room to spread out, and when I am finished, I have a small four drawer chest I keep near my chair, and it holds everything I use.
I recently got a secretary desk and I am in love with it! It's so handy to everything right there in the cubby holes but be able to close the lid when you want your living room back.
the armoire idea is extra attractive because if there is one single item of furniture it seems like people are trying to get rid of on craigslist, it's entertainment hutches--probably due to the advent of flat screen wall-mounted tvs. you can take your pick from so many for so little $$!!
As long as the staircase is not an open tread staircase it is a great space for an office or sitting/reading nook. I once lived in a place that had open staircase & the dirt & dust that would come off the stairs & onto my little loveseat/reading nook was horrible!!! Made it no fun to relax in! I temporarily solved the problem by affixing & draping fabric under the stair case to catch dirt. Needed to take it down occasionally to shake out & wash. Yuck. Such a pain. No more open staircase concepts for me!! So imagine an office space with computer under open stairs getting all covered with shoe grime/dust bunnies, etc!
Where I am at now I use a cool old Mexican painted wooden kitchen table in the corner of my kitchen as my "office space". I had a friend build a hidden shelf below the table top to stash my laptop & other things to quickly get them out of sight when people are coming over for dinner or coffee. The table can then also double as an extra eating area.