Oxalic acid does the trick on rust. I like Simple Green for cleaning/degreasing. PB Blaster is great for stuck parts/nuts/bolts. It also works great for cleaning the really grimy stuff, though not a very cost effective solvent. Meguiar's ScratchX 2.0 works great on the paint. Mothers Mag & aluminum polish for the aluminum stuff.
~kn
EDIT... Didn't mean to parrot you Bob
