http://shiggsy.gbadev.org/unit.php?unit=51 I can't find any other thread about it, and since I've bought one of these some times ago but nobody has been able to explain me what the hell I've bought...if someone describes me what is that, I'll reward him with eternal gratitude!!!!
here goes. the EXI connector , found on all gamecube and final ORCA mother-boards (as a daughter-board) is the connection standard used for operating memorycards, and the USB2EXI connector (provided that code is written for it), as well as the Microphone accessory. Think of it of a USB port of sorts (in very very general terms). This is the prototype daughter-board, as depicted in my friend Shiggy's site, and is indeed a very interesting item. There is nothing you can use it for at the moment however. It;s a piece of history nevertheless!
It's a prototype of the "bios / RTC" rom. My guess is that the emulated rom content can be written using the parallel port into the attached SRAM (in the sockets). The pin headers probably connect to the EXI bus.