I needed somewhere to hang my headphones when using my computer which is next to an Ikea Lack side table which has my 3D printer on. So i designed a simple mount that would slide over the side of the table. I have put double sided tape on the inside of it that touches the side of the table, this holds it solidly on the table.

The top area where you place your headphones is roughly 40mm from table edge to stand lip and 45mm wide side to side.