http://www.makershed.com/SearchResults.asp?Cat=20
use code: MKHCKR on checkout and get 10% off - this is one of the few/best deals on arduinos and electronic kits. we now stock the new arduinos too.
this expires 12/1 - hope this wasn't spammy, i'd like to see more folks build cool projects.
if you're interested in the biz model behind open source hardware, wired has a good article... http://www.wired.com/techbiz/startups/magazine/16-11/ff_openmanufacturing?currentPage=all
and here's a presentation i did about open source hardware too: http://blog.makezine.com/archive/2008/11/open_source_hardware_over.html
http://blog.makezine.com/archive/2007/04/open_source_hardware_what.html
cheers!