The UnderArmour 7-inch compression shorts don't ride up at all.

I think they are my all-time favorite for riding. They make nice undies under skirts and trousers as well. (don't need a slip with my unlined wool skirts if I wear the UnderArmour)

They dry very quickly, so no need to change when you get to work. If they get permanently stinky, wash them in dandruff shampoo. It really works.