I don't know that I would go with the "green zone" but Bike Friday makes a pretty nice folding bike... wait... no... fuck you for even thinking about it... In fact fuck you onemillionbillion times in the face!
Actually yes, you should get one.
Try riding one first. They are SUPER squirrely! All 20" 'road' bikes are. If its for traveling, I sugest couplings.
check out these bikes. Ive been looking at the strida for a while, just cant justify it right now. And it's a single speed. http://areaware.com/productlist.asp?CatID=15