What to do with old vacuum tubes?
I recently found a really old tv in a crawlspace at work and I brought it home and salvaged 13 vacuum tubes out of it. I figured I could make some sort of cool project out of them like maybe a mad scientist lamp with LEDs or something. But before I actually start using them I wanted to brainstorm some more ideas of possible projects. So if anybody has any good ideas of cool things to do with vacuum tubes, let me know. Also, just out of a nerdy curiosity I was wondering what exactly vacuum tubes are designed to do, does anyone know?