There are two main advantages I see in the RasPi, over pretty much anything else:
(1)Low cost/power. As mentioned before, its a cheap, low-power computer that you can easily make into a media center, a little background-downloader-thingee, a paperweight...
(2) Its brick-ability -- Or rather, lack thereof. You can do pretty much anything to it, software-wise, and always be able to recover. So, if there are any cool things people put on the forum that you want to try -- I believe someone is working on making it an NES emulator -- then you can try it, with no more tech knowledge than how to copy some image onto an SD card. If it works, then you have an NES emulator. If not, then you still have a fully functioning RasPi, that all you need to do to reset it is to take the SD card out.
Or, if somehow it actually manages to harm the RasPi permanently, then point (1) comes into play, and you can get another one for $35, tops.
Plus, also, it lets you feel like a really hoopy frood for having given $25/$35 to an uber-cool non-profit.