If you want to ruin your life, and destroy your sanity all in one prop, then make an Axeworthy Ghost system. However, if you build one and get it to working, it's about the coolest thing you can imagine.
The second part (would have made it all one movie but didn't know I had Windows Movie Maker for Windows 7 until this morning) showing the tension wheels...
I cranked it up last night...it was mesmerizing. I placed a black light pointing upward in the ghost's path and as it approached, it recharged the glow paint and glowed bright green and then slowly faded as it rounded the loop (about 225 feet), before recharging again when it got to the blacklight again.
Then it derailed and I went inside and watched I Love Lucy.