First post, hope I can be of help. My wife and I pretty much collect flashlights. We get frequent power outages and over the years we've tried nearly everything to see what works best. However, what works in one scenario doesn't mean it works across the board. The Infinity Ultra Task light is okay in the house, but in the yard (we live in the country; very dark at night), or when camping, it's not the best thing to have. The earth/foliage soaks up the light and I would not want this as my only light if I was in a mountainous area -- it simply doesn't cast the beam far enough. The Fenix goes an hour and a half if I remember correctly and I no longer think that adequate when out and about. An aquaintance of mine, a physician and avid big game hunter, had a harrowing experience near cliffs in Alaska when his SureFire light went out after an hour. I think 3-4 hours is the minimum for taking abroad or when backpacking/hunting, etc. Until recently I used SureFires for tactical applications and an Underwater Kinetics 4AA or 2/DL123 light for everything else, but a recent arrival on the market has forced a further change.
Try the new SureFire G2L. It's a LED light with about 12 hours of usable light. It throws about 75 lumens for a couple of minutes and then drops back to 65 lumens for a number of hours. LED's throw a very white light, unlike the yellow tint of incandescents, so it takes some getting used to, and I don't think they work nearly as well in smoke/fog, but these new G2L's have overcome that somewhat. They still aren't as good as a 9P, M4, etc, in the Surefire line, when distance/smoke/fog are involved, but the lumens are very impressive and work WAY OUT THERE (as in 50-60 yards) when compared to the Infinity or similar lights. Add the superior battery life, no need for $20 replacements bulbs like the incandescents, and the reasonable price, and you have a pretty good solution. I think we paid about $50. It was well worth it. I intend to get a couple of more to put in each car. I've tried them outdoors and they are light years ahead of the smaller lights mentioned, yet still small and light enough for travel.
If that is too big, look at the Princeton Tek Impulse. In the last couple of days I compared it to the aforementioned Infinity light I had next to the bed. It clearly outperformed the Task Light. It has low/medium/high settings, plus two flashing modes. I was so impressed with it, I put the Infinity away. I think we paid about $13 for these at REI. They have a 12 hour battery life on high, 24 hours on lmedium and 36 hours on low beam. Now I haven't tested this yet, it's what the factory printed on the box, but even half that time, considering the amount of light on high mode, would be adequate for travel. The neat feature about this little light is that it attaches to your shirt/pants and also comes when a mount to put on a hat.