this isn't really a project itself, but merely part of a larger project
I recently purchased a few dozen 'pirahna' style leds ... otherwise known as P4 or High-Flux/S-Flux
as far as subjective non scientific observations go, they are noticablly brighter than several round 5mm leds combined
I made a few 'piranha pods' that i can try out various places, and easily daisy chain in a parallel configuration
testing all 3 colors

frontside
[img width=640 ]http://www.manisteecomputers.com/video/piranha_pod_front.jpg[/img]backside
[img width=640 ]http://www.manisteecomputers.com/video/piranha_pod_back.jpg[/img]