Here's a little illusion I figured out with TNT, a big pit, maybe some water in the pit, a dispenser, and a redstone clock. The dispenser is just constantly dispensing TNT into a pit filled with water so it doesn't explode. Why the pit, and not just water? Because the TNT will launch each other into the air (kind of) and blow up your machine.

Additional Notes

Incase you were wondering, I called the map "by galika1080" for a reason. It'll look way better in- game, don't worry.

**WARNING**
There is a very small chance that the whole thing will glitch out and blow up in your face. I think I worked out that bug, but you can't be sure, so just be ready to be blown up and have to unzip a new file.