Both the NAND and the NOR gate in one world, the same as the AND and OR gates, but the conditions reversed.

NAND : If both inputs are ON, the output is OFF, else the output is ON

NOR : If any input is on, the output is OFF, if all inputs of OFF, the output is ON

Youtube channel : http://www.youtube.com/user/ObedientRedstone

If, you're planning on trolling, this is just the simple stuff, give me time to get to the more complicated stuff.