Rusty/Stuck Bolts

[Stumpalump]

I keep two spray cans of lube around. One is CRC cutting lube. It's a foam that clings to a drill bit and it just works great for drilling holes in metal. For everything else there is only one can needed for things like guns, bike chains, small mechanisms or as a penetrating lube. Tri Flow in aerosol cans. Grainger stocks it in full size cans. Both will last a long time since it takes so little. You will never go back to PB Blaster, WD40 or any other lube again.
http://www.triflowlubricants.com/Superior_Aerosol/superior_aerosol.html

 

[Will Riggs]

Look into a product called trick shot. Amazing penetrant.

 

[brp]

There are also nut splitters, they work OK, and can get in tight places. I have used mine a few times and I am glad I have it.

 

[zukimoo]

Best I ever found was Solvo Rust from Loctite. I sold a lot of it to restoration places and have found that if you can let it sit overnight it works best.

 

[aythya]

Another vote for Kroil products: Kroil, AeroKroil or SiliKroil are all by far the best I've ever used.