Among other things I think it's the huge rush I get when I figure out something hard. Can't be beat :) Then there's the satisfaction of imagining a system and

Among other things I think it's the huge rush I get when I figure out something hard. Can't be beat :) Then there's the satisfaction of imagining a system and slowly putting it together. The exhilaration of a new program. Problem solving at different scales. The anticipation of a finished application. All good. Not to say it's all fun all the time, but I don't need to be paid to want to do it :p