If you like the funky color things that happen with odd color lights, like mixing tungsten and daylight, then why not go nuts and try some bright colored gels over your lightsource?
In this group, all we did was goof around with stronger and weaker color gels on Nicole's left and right to see what happens.
We used the HONL system which comes with a nice filter kit, both for color balance correction as well as strong color effects.
Bottom Line: It is so easy to put a tiny colored gel on small flash that it begs to be tried.
105mm, f 4.5, Speedlites with colored gels, ISO 200
(This page could have been part of the Small Flash section, but since you can color any lights with gels, I decided it is more about light than flash.)