what it uses up: strips in any length and width
Perhaps the easiest thing you can do with strips to use them up - make a strippy quilt. This is a small baby quilt size example, but you can make much larger ones if you like. Not only do the strips not have to be all the same width, but it actually looks better if they aren't. And they don't all need to be long enough to go all the way across your width - you can piece them together. I recommend you do so in some rows even if you don't strictly need to, as it adds to the texture of the piece.