The stock LED MagLite 2AA is a great light for the cost. I'm not a fan of the variable focus head, as I can never get it focused well for throw (vs flood).
The niteize comment reminded me of this.
I carry a Photon Rex as it's rechargeable with any 1.5v battery, and bright enough for close in work. This is on my key-chain. If I carry a light, it's a Surefire E1B Backup (which I just saw in silver which is very handsome).
At home I use the Maglite LED 2AA, both variations of the Photon Proton, and a Pak-Lite (a tiny 9v, 2-led light and great runtime.