How much money do you want spend? Cygolite Metro cost $48 and will last up to 5 hours on a single 6.5 watt beam (either flood or spot) and the battery bag straps onto the frame thus freeing up your water bottle cage...but it uses 6 D bats which a lot of people don't like though I do; you can use either throwaways or rechargeables.

If you like the AA battery concept then Performance sells a compact light called the ViewPont Gen3 digital with 6 light settings that runs up to 5 hours on high with 4 AA's, this light is supposely equal to a 10watt halogen but probably closer to 8; this light cost $140 but now on sale for $100; http://www.performancebike.com/shop/...tegory_ID=4320. They also have the same light except non-digital that can run up to 8 hours on high but with 2 light settings (not sure if the digital is brighter then the non digital, you can call Performance and ask if you need to know) and this one cost only $60 but on sale now for $40. http://www.performancebike.com/shop/...tegory_ID=4320

Either one of the ViewPoints would be brighter the the Cateye 500.