I recently purchased the Presidian USB Desk Lamp (Model 61-126) from RadioShack for $19.99. This desk lamp is powered by either USB cable or AC adapter (both included), and is a very versatile little lamp. I use it as a reading lamp, and it works quite nicely for this purpose. It has a cathode fluorescent tube which is rated at 10, 000 hours of bulb life. It also has a flexible gooseneck which allows you to adjust it in various ways. The only drawback to this lamp that I have found is that it is somewhat top-heavy. I have to adjust the gooseneck a certain way to keep it from toppling over. But the lamp has come in so handy for me that this problem does not really bother me that much. It comes with a limited 90 day warranty, and I have found it to be a very versatile lamp. I like the fact that I can also use it with my computer. If you are looking for a nice little lamp either for computer work, reading or close work of any kind, this is a nifty lamp to use. I purchased it in a pastel blue color, and I believe it also comes in another color as well.
Update On Mar 02, 2010: I am happy to say that this little light is still working for me. Every once in a while, the light flickers. I'm thinking I may be reaching the end of its lifespan, but it still works and has lasted me a long time, which was a nice surprise.