I saw several vendors displaying long flexible strips of LED lights, as seen in the video I shot at CES. They all seem to run on 12V power sources, so they would be adaptable to bicycle use. One vendor had strips that changed colour in waves, but those required a controller about the size of a Twinkie.
Pilot EL-Tech (Shenzen) Ltd displayed the multi-colour strips.
logisys also had single colour LED strips as well as the products.