As a emergency torch take a look at the "forever flashlights", e-bay for around a fiver, no need to pay more than a tenner... You shake these which causes a powerful magnet to slide back and forth through a coil, the resulant electricity is stored in a capacitor and powers a white LED. 30s of shaking gives a good 5mins of light. Ceratinly no batteries to go flat or filament to break should have good life. They are also waterproof and float. The 5mins of light is perhaps not particulary convient but is better than nothing.
Thats the one where you turn a handle to operate a dynamo isn't it rather than the orginal Freeplay clockwork radio.
CostCo had an instersting looking lantern the other week. Claimed 16hr battery life of D cells. Small flourescent tube as the light source, I was tempted...