Basic Stamp
http://www.parallax.com
PicAxe
http://www.rev-ed.co.uk/picaxe/
http://www.stepsystems.fi/tuotteet/picaxe.php (FIN)
ooPic
http://www.oopic.com/
http://www.esutech.com/OOPic/default.shtml (FIN)
Arduino (open hardware project)
http://www.arduino.cc/
check the clones as well
CATKit (open hardware project)
http://packets.goto10.org/packets/wiki/CATkit
Check also:
• Atmel microcontrollers
• Texas Instruments microcontrollers