The XAND discussion on the C++ board made me think...
First, if there is actually an XAND, like Shiro says, what's its truth table?
Secondly, in my digital circuits 1 course, we were told that any digital circuit could be designed using a standard NAND gate (well, a LOT of standard NAND gates)... If this is true, how would you design a flip-flop from them (we'll just say a J-K for simplicity's sake)? Also, would there be a way to create the clock needed to drive one using standard NANDs?