I seen some of these in Fry's back by the computer cases. They're kinda big though.
http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 47837&rd=1
They're all over
You could rig up your own though. It's just a light, a revolving reflector, and a colored dome. A flash light has the reflector and the light, so that's the easy part. There's motors all over the place, so you could mount it on there. The dome could be made out of what ever you find that has that shape. Doesn't even have to be a dome like the old ones. you could use some square boxes and make a newer type of light bar.
http://www.specialtybottle.com/index.as ... ProdID=206