We used to work on a lot of carnival rides and equipment. We used 3,4 & 5 pole chaser units. These make the poles flash in a sequential order continuously so the lights look like they are moving down the line. They are electronic now (they weren't always)& almost dummy proof to install. They have one feed, one neutral and a bunch of switch legs. Most only flash the poles in a constant order tho. (i.e 123123123123etc). It's been a while since I had to buy one and being old I forgot who we got them from. Try a yahoo search for "carnival suppiles" or something like that.
Good luck
