I have thought about this often, and I am assuming a long life :) (If I knew I only had three years to live, I wouldn't want to give up one of them! :) ) When I look back at my life, the times I miss the most are when my children were young. I would pick a day, a Saturday when they were all home, when they were 3, 5, 7, and 9. The three-year-old was old enough then to be out of the "baby" or "terrible two" phase, the 5-yr-old was just at an incredibly cute phase, the 7-yr-old was transitioning to the "no longer a kid" phase, and the 9-yr-old still openly loved me (those of you with girls, know what I'm talking about :) ) I look back at all the old photos and can't believe how fast the years went by! I think the greatest power in the world would be to be able to look at any photo, and flash into the scene of the photo at the time the photo was taken; a combination of time travel and life repeating :) (but could get odd if you flashed into a scene that you were in :) )