The feet here are made with a simple bandsaw trick that allows for angled cuts on all sides. Of course, lacking a bandsaw, straight feet, recycled steel couch legs, or little bits from the hardware store would work just fine. Feet are essential, though, as they keep the thing from looking less like a cabinet just set onto the floor and more like a piece of furniture.
I used pallet-scrap oak. Lots of pallets
are made from hardwood, due to the weight they have to bear. Once you have a piece de-nailed, run it though a planer and a table saw to square it up as best you can. Cut four 4"-long blanks. Then, using a bandsaw, cut two angles on the same face, per picture 6. You could stop there, or . . . use masking tape or painters tape to put the cut pieces back on, re-assembling your original block. Rotate it 90 degrees, scribe identical angles onto it, and cut them away. You end up with a radically angled foot, tapering in all four directions.