For black friday (the day after thanksgiving here where stores have enticing sales) I've seen GBA micros for around $30. Not sure what they cost now but I'm sure they are less than $50. You can get the old style GBA for less than $20!
I m very interested in a second "strong light" edition of GBAsp and/or a cheap Micro. If anyone can find any of these for *cheap* in any US stores, please do mention, as I might have a task for you ^_^