I've started commuting by bike again after a decade in the cars. I remember back in college I used to spray my mountain bikes down with WD-40, but I don't know where the devil I got the idea of using a degreaser to protect bike parts! This time around I've been using M-Pro cleaner on the chain and CLP on the external metal parts. They're designed for firearms but seem to be doing very well on the bike at protecing it from water damage and keeping things lubed without getting gummy. The problem is, they're very $$ and I'm thinking of going over to cheap household oil instead. What are other people using?