A great gift idea for a sixteen year old boy aside from a video game would be something for a car. You know he either has a car or is dreaming of getting a car and his license. Put together a car care kit with a bucket, sponge, wheel cleaner and air fresheners. Or maybe have a license plate made for him. Boys that are going to be driving will also love a gas gift card. This will give them freedom to try out that new license without putting a dent in their wallets.
Honestly, unless you really know a person well, and absolutely know what a person wants, in my opinion giving them a material gift in this day and age is almost pointless. It's way too risky that the person won't be all that interested in it. And therefore, asking strangers on the Internet what to give a person, whom definitely don't know the person at all is not the thing to do.
If you live in a first world country, and apparently you probably do since you have already referred to a video game, then money is the best thing to give if you're not absolutely sure what they want. Then they can go out and buy whatever it is they want. I can't tell you how many gifts I have sitting around that I have no interest in, and the people who gave them to me just wasted their money.
In my opinion, gift giving is an outdated tradition that is growing obsolete in this day and age of plenty where a person can buy whatever they want with money. In the past, when you couldn't get anything you wanted by ordering over the Internet, or any other various means, material gifts carried much more meaning.
So don't ask strangers what to give something to a person we don't know. Either find out from him what he wants (or from someone else who knows him well), or give him money. Otherwise you will be taking a huge gamble that your gift will not be well received by him, and he will wish you had just given him money.