I found an interesting little note at HTLounge.com. It seems you can now try out the "stripped-down" Linux that runs on the machine that One Laptop Per Child is shipping to third world countries.
The writer concedes that there's no real reason to "downgrade" to such a basic OS for use when you're running Mac OS X or Windows Vista (or when you're running Vista on your MacBook). But, it's valuable if you're interested in building applications that will run on the OS. Curiously, though, he doesn't really explain where or how you can try it out.
After a little digging, I found helpful links here. If you check it out, let us know what you think.