Bill in Stratford, Ontario sent in this great tip.
When you just need a touch up of paint or stain, rather than opening the lid and increasing the clean up problem, simply punch a hole in the top of the can.
You can cover the hole with a finger to shake the can if you like, even use your finger to apply that little touch-up. Then simply tape the hole shut with some duct tape. If you fold one corner of the tape over on itself, it will stand up from the lid to act as a handle for opening the hole when you need it again.
Worried about evaporation? Use aluminium or plastic tape.