I upgraded my old 3xD cell MagLite with an LED emitter. It's way too big and bulky to carry around, and it's not bright enough for anything but close-up work. However, it makes a great troubleshooting-the-sump-pump light, as it survives horrific abuse while providing long runtime.

(I'm not picking on you, Phaedrus, I'm just incapable of not commenting on a flashlight thread .)