I have a NiteRider MiNewt.250 cordless LED bike light with a rechargeable Li-Ion Battery. It has a low-med-high setting or a strobe setting that I use during the day (even when it's sunny) to get people's attention. In the back I have a Planet Bike "Superflash" which makes a crazy random type wild light pattern that is attention grabbing. I don't ride at night much, but even during the day lights (like cars whose running lights come on automatically), I use them. You can never be too careful.