I've been using a Dell Mini 9 as my primary development machine for over a year now. There's more than enough power to fire up emacs, chrome, and a jvm (we're a JRuby shop). I love the amazing portability, and the ergonomics are adequate.

'Piece of Junk' is in the eyes of the beholder. In my experience, a $300 netbook has been the most productive machine I've ever owned.

edit: Sorry about the dupes, for some reason my phone freaked out and sent this three times. Fixed now.