Slashdot had an article yesterday about the One Laptop Per Child CEO (who has a PhD in optical engineering and designed the OLPC's screen herself) founding a new company to build a $75 laptop.
I think the OLPC project was originally called "the $100 laptop". The idea was to create a computer that's so cheap that you can use it to bring computing infrastructure to poor countries or even places without any computing infrastructure at all. (And yeah, it runs Linux). It's small, cheap, low-power. After flipping through some of the linked articles, and my recent search for a small, light laptop, I thought to wonder if I could get one for myself.
Well...OLPC is designed as a charitable organization and is optimized to accept donations and to supply laptops to governments who wish to have them in large batches...so they're not really equipped for single retail sales. However, there was a program set up called "give one get one", which meant that for $400, you donated one laptop to the cause and got one yourself. Unfortunately (or maybe fortunately for my discressionary spending budget) that program ended at the end of 2007. And, no surprise, searching ebay for "olpc" gives 49 for sale. :-) There's a black market for anything.
In any case, I'm not sure that I really would want one, but it's an interesting point in the parameter space of very low power computing.