Do you build anything for your high fidelity system? If so, what do you make?

After some self assessment and introspection on my own high fidelity habits I discovered that I build or make things for my stereo/audio room. Some examples of these things are;

1 Tore out carpeting/padding/floor tiles in the addition to my house (audio room) and painted the cement floor with epoxy paint and clear coat. Placed out a Turkish area rug.

2 Made cherry wood speaker stands on wheels.

3 Had made custom speaker covers and stereo stand covers for when I am not listening to audio to keep away dust. Thanks to my seamstress....

4 Custom made Paduak wood cover (with legs) with two low speed exhaust fans for my tube amp

So curiosity got the best of me. Have you made anything for you stereo system or room? If so what did you make and why?