http://www.ebay.com/itm/2012-3x-CREE...item3ccc0be535
This has three of the leds that are in my single LED Cree XML-T6 light which is already super bright. I'm thinking of buying two.

Also this:
http://www.ebay.com/itm/Cycling-Bike...item231c7054c4
I'm thinking two for the heck of it just because they're so cheap.

Is it a good idea? I already have a super bright light, but it's like chocolate cake: I want more lights. MORE. MORE. Never can have enough. I don't just use them for the bike though; I use them for camping. I was thinking of having all three lights on a headlamp, so I can illuminate the entire campsite if I wanted.