Being a bit of a sucker for gadgets, (especially camera related gadgets!) these filters caught my eye from the always innovative, Photojojo
The Color Lens and Flash Filters! Eight vibrant, pocket-sized color filters on a handy ring, ready to use over your lens or flash.
Get color-creative in two ways: shoot with the filter over your lens or shoot with the filter over your flash. The first adds color to the whole scene you're shooting (ex: the whole ocean turns red!), while the second adds color to only the parts that your flash hits (ex: only the guy standing in front of the ocean turns red, and the ocean stays blue!).
At just $15 I think I will be adding these to my wishlist :)