My printer tends to print a little 'short' of a full page at times - so I have a blank gap. For art journal pages this is a bit annoying, but I was very pleased with the results of using a strip of black dotted washii tape along the bottom. It fitted in perfectly, and for this printed page, it just added the right amount of subtle interest.
If you collect old papers, you could cut a tape-like strip of text, and paste that. Having a ragged top to it could also work well.