They are quite inexpensive, cheap ones hanging in auto stores, Target and Wal-Mart. The better ones have remote control, which is quite neat, imagine if you can turn on the neon lights outside the disco. I think $100-$200. If you search eBay, there are lots of them. I thought about it but gave up on that since I couldn't figure out when or where I may use it. I saw a truck with it light up in LA last week, looks very cool.
If I know how to install them, I would buy a set.
I think for offroad use, the tubes will be broken within the first few minutes.
$9. Up for sale are 12" Single Cold Cathode Units with Inverters, in 6 color choices.
Available colors are Blue! Red! White! Green! PURPLE and UV (Black)!
Included with the purchase: 1 (one) 12" Cold Cathode bulb with polycarbonite casing, and 1 (one) 12volt Inverter. The bulb comes ready to connect to the inverters. This is a great do-it-yourself kit for auto enthusiasts.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2451848462&category=33 714
There are tons of them here.
http://listings.ebaymotors.com/aw/pl....html?from=R11