If you (or know someone) use the roller ball type deodorant, when it is empty if you force a blunt (butter type) knife between the ball and the top edge of the bottle you can `pop' the ball out, then you can wash out the bottle and re fill it with liquid paint then put the ball back into its housing. Now you have a unique painting tool to create backgrounds etc. you can even `write' with it. If you fill the bottle with glue (not too thick) you have a glue roller. These are especially good for young children to paint and glue with saves a lot of spillage and general mess.