An eight year old is probably going to use the light mostly for playing. Heck, I am 58 and a lot of what I do with lights is playing. I see that several have recommended the SF G-2. Would you really want to give an eight year old a light that the replacement bulb (P60/P61) will cost you from $16.00 to $23.00? Actually it will cost you more than that when you add shipping. The replacement lamp cost more than half the price of the flashlight. You could go with a Streamlight Scorpion for about $30.00. The Scorpion is a little brighter than the G-2 (P60) and Scorpion bulbs are just $4.50 each. You could also go with the a Brinkmann LX from Wal-Mart for $20.00 and bulbs for it are just $4.50 also. I am not saying the G-2 is not a good light. What I am saying, is that what you want the light for, there are lots of better choices than the G-2 (IMHO). Personally I wouldn't give him a 123 battery light. I would go with something that has a decent run time (over 2 hrs.) and it would use common alkaline batteries.
I have never met a kid that did not like flashlights. Every Friday on my way home from work I pick up my grandson (age 6) and he stays with me until Sunday. We "play" flashlights a lot. We go outside a shine them up in the trees. We go in the back yard and play catch your spot (like tag only with flashlights). We even made up some games to play in the house with them.
James