Using up oddments of plain paper also works in the same way - I cut them into strips and paint a little scene on them. Sometimes it may only be one colour with no picture, just because I happen to like the colour. They are ideal as bookmarks too and can always be tidied up and squared off neatly then laminated and given as a gift.
With this in mind I was playing with some oddments yesterday and ended up using my finger as a 'resist' on the paper. I then painted over with Cobalt Blue watercolour and turned one into sheep and the other into robins.
I added these to Sketchbook Challenge - Can't Resist This! They were a bit of fun only but I have eneded up with one or two comments about the idea and hopefully this will inspire others to have a go and use up their oddments of paper rather than throwing them away.