The perfect Flashlight? I have no idea, however I can make a pretty good argument for them being high on the list.
They are readily available, have a wide price range (you can even find them at the dollar store), with few exceptions (one is listed below) they are silent and lend themselves to both active and down time. Type flashlight games into Google and you'll find all manner of outdoor fun: tag and hide & seek - much more fun with a flashlight. Blow bubbles at dusk and attempt to find them with your beam of light, they glow!
At the same time you can crash on the living floor and play flashlight tag on the wall or practice your shadow puppet skills. They can be comforting to the kid who's wary of the dark, some even convert into soft glow nightlights and would be much appreciated by the after dark reader. Perfect for sleep-overs, pup tent in the backyard, basement fort and a necessity for sleep-away camp. Inexpensive enough to make great additions to party goody bags and Christmas stockings. Convinced yet?