no no no guys. First of all Flash cards don't work, don't waste a penny on flash cards.
The memory card has to be SRAM, if it isn't, it won't work, period. The 2k attribute won't really do anything, it is not needed, and usually is more, so just go for standard SRAM. Any size seems to work, but it is formated by the Neo Geo... I don't know what size it formats down to, I never checked... it may be formating a 8MEG card to 12k, I don't know
Anyway, for the record... PCMCIA SRAM card will do the trick!
-Nick