Here we go, nice dev and test stuff up for grabs.

Please contact me through PM when interested, the more you buy the better the price!
I am always open for offers as long as they are reasonable.

FAMICOM Testcart, very hard to obtain, hardly seen. $250 OBO
NES Neotoxin, homebrewn game. $100 OBO *SOLD*
NES testcarts, all authentic, one has a replaced label though. $175 each OBO *1 SOLD, 1 LEFT!*
NES devcart, used for testing loose chips. $135 OBO *SOLD*
PS prototypes/ samples, hardly seen and in good state! $ 35 each OBO
DC prototypes/ samples, hard to obtain and cool games. $35 each OBO
N64 Wide-Boy for GBA games, including manual, unreleased! $250 OBO


Pictures: http://img.villagephotos.com/p/2009-11/1349008/0

Sorry for digging this up if none of this stuff is
available, but PM sent regarding the Wide-boy.