The iQue Card is a removable memory card used to store games & the "Upgradable Operating System".
The card is housed in a plastic shell, which contains a Samsung K9F1208U0M-YCB0 NAND chip on a special PCB codenamed "DOOKIE". The contents of the NAND are documented on the NAND page.
The DOOKIE board is very basic, containing the NAND flash, a few resistors, and an edge connector for connecting with the main system. The connector has a 1.1mm pitch and seems to be custom made, no other commonly-available connector appears to fit it, other than MicroSD.