In search of inspiration (or "why use silk when you have cotton?")

I seem to have built up quite a collection of cotton yarns...  Two in particular are taking my attention at the moment, where I've got a few balls to work with but just don't know what to make from them.

First, there is the yarn from an unsuccessful lace cardigan I was making myself a couple of years ago:

I got the decreases wrong for the sleeve and couldn't work out how to fix without starting over, so now I have 6 balls of green cotton dk yarn without a project.

And then there are the 6 balls of cotton 4-ply which I bought for a song from a local shop's bargain bin:

I'm using some to make a stretchy market bag, but I'm stumped for how to use the rest.

Neither yarn has a friend to go with them, and I don't want to waste the larger amounts I've got... so I'm in search of some inventive ideas for my cotton stash.