Of personality.

I've always found it somewhat ridiculous that some RPGs require extensive descriptions of one's character personality. Certainly I can see and understand their reasoning in terms of weeding out the worst of malformed personae, but typically it is required to be fairly extensive. Should not personality be something shown, rather than told? (I'd rather show you than tell you, Mr. GM. Meet me at this address at five-thirty, in the alley by the dumpster...)
Hence, in these uncomfortable situations, much of my characters' personality is normally left untold, apart from that which is not revealed by their actions.