Yeah, my keyring one is the best tiny light so far. The iTP A3 EOS. It throws out about 100 lumens on high, is about as bright as a mini Mag on low (and will stay on for 90 something hours on low) uses just one AAA battery and is about the size of your pinky. About $20.00 unless you get it in titanium for $50.00
Nine mile skid on a ten mile ride. Hot as a pistol but cool inside.