Litter box cover from 2 IKEA side tables and fabric! This is a great DIY for cats, better than traditional covered boxes because it doesnt have plastic on the sides, which can trap odors and make some cats reluctant to use the box as often as they should.
Here's a cool DIY idea for a cat enrichment toy. Glue together a group of toilet paper rolls inside a tissue box and randomly fill the tubes with treats. Your cat will be stimulated when they "hunt" for a treat. So simple and inexpensive.