Had a walnut offcut about 25 x 15 cm lying around for months. Keys and coins always end up scattered on the shelf by the door, so: tray.

Marked out a rounded rectangle with a 1 cm border and hogged out the middle with the trim router, about 12 mm deep, in several shallow passes. First time using a bowl bit. Went slow, still got a bit of tear out at one corner which I sanded out.

Sanded up to 240, then four coats of oil, one per evening. Glued a piece of cork sheet to the bottom so it doesn't slide.
Next to nothing in materials, maybe 3 hours total. Probably the most useful thing I made this year.