Lights

Not super cheap, but good non-the-less - CLICKY. I've got one of the original halogen light units.

I swapped the bulb out for a 35watt one (from ryness) and bought a flightpower 3cell 11.1v lithium polymer pack off 'the bay' - which i charge with one of THESE.
Connection between the light and battery pack is with the supplied power cable - which i've added a DEENSconnector to.

I keep the pack (which weighs nowt and lasts for yonks) and connection in a neoprene phone sleeve which i attach to the stem with a velcro strap.

If you're riding in heavy rain the pack really needs to be in a couple of sandwich bags to keep the rain out - lithium and water - now that'll give you a nice bright light…

Obviously a Tinker(er)