I used to use them for all sorts of stuff. Leave the cap off, once empty and it will crystallize and dry, bounce it off the bench and dump the bits out, give 'er a quick rinse with varsol or brake cleaner and hit 'er with some compressed air and away we go.
I liked them for putting hydraulic oil into a truck that was too far away from our pump.
Our lead hand at the last place I was at used them to steal gasoline from the shop fuel pumps for his own personal vehicle.