Use a spoon to pry up the lid edge
Rub the lid on concrete or rough stone until it wears through
Strike the lid seam with the back of a sturdy knife
Cut around the rim with a strong kitchen knife
Use a screwdriver and hammer to puncture the lid, then work around the edge
Clamp the tin and saw through the lid with a metal file
Use pliers to twist and tear the top open
Heat the lid briefly and then pry it up with a tool
Use a church key or bottle opener if the tin has a lift tab
Ask for a can opener from a nearby person or place