You already know that you can make practical things of wine corks. For example, wine cork bath mat would be a great addition to your bathroom, trivets made of wine corks could become a great addition to your kitchen and so on. Although you can also make an artwork from a bunch of such corks.
To make such artwork you’ll also need a frame. You can make or buy it. The idea is simply to glue in wine corks in an interesting arrangement on it. It’d be a good idea to cut one side of the back of each cork to make it flat.