Ask HN: What's your favorite embedded system?

I'm looking for something rugged, capable of running Linux, and cheap if possible. I'm just curious what you guys have actually used and liked as I evaluate which one would work for me.

I've used this in the past but I'm curious what else is out there: http://parvus.com/products/MilitaryAerospace/EmbeddedBoards/CPU-1421/