Free ideas and DIYs have always been the point of this site, here’s another DIY on how to make an under-the-sink Cat Litter Box. Well, actually, it’s not really a DIY, you just pretty much put a cat litter box under your sink, that’s probably it.
My husband had the idea of using a lidded storage box, and we found the perfect item in the Ikea Snalis storage box. We cut out an entrance with a utility knife, and we originally had a plastic mat as a door — which our cat hated, so now we just leave it open. There is plenty of room for our big boy inside, and its flat lid fits under the sink perfectly. It’s a tiny little hack, but it works great!”