Yep! Tax cheats, drug smugglers, and insurrectionists also come to mind.

Already written... See The Dice Man by Luke Rhinehart.

Half the businesses in the country still run on it. Lot's of the original code was written by the owner's kid(s). Guaranteed, you'll see coding choices you never imagined :-). If you ever fell in love with VB6 you'll be right at home.