Silva Ninox 3. 300 lumens, waterproof and an excellent deal (available as low as £19.99 if you search online). Only downside is it doesn't work with rechargeable batteries, only normal ones.
I've got a petzel reactik and have found it to be very good. Bit more expensive but very good. It changes its light output depending on light source and terrain.
I have the Petzel Reactive + and have to say I'm very pleased with it, i normally run with it on auto mode so it adjusts the light depending on darkness. I use mine for trail running.
Just got a Durite head torch, LED strip on the front and 2 brightness levels. Best of all it has a sensor that allows you to turn on and off by waving your hand in front of it. Also has a USB charger so no batteries to worry about. Cost approx £23
Comments
cheap'n'cheerful
or
https://www.decathlon.co.uk/onnight-710-trail-head-torch-id_8370255.html
bit more powerful
http://www.agmpartscomponents.co.uk/durite-0-699-60-led-rechargeable-head-torch-3w-led-cob/
Shows £33 but can get cheaper.