it's the little things like the tops of allenkey bolts, limit screws,
Pot of vaseline, get a dollop on your finger and push it into each socket on your bike, including philips screws on derailleurs etc. You'll hear a 'pop' as you push the vaseline in on the first push (sorry guys, trying to not make this sound like a sex act), then do it again to make sure the socket is full.
Vaseline is best, because when you do have a need to undo said bolt in future, you'll no doubt get some on your hands, just rub it in

Also, vaseline doesn't turn liquid. I do this on my bad weather bike.