For science I recommend either Science or Nature. I've had subscriptions to both in the past and preferred Nature, not really sure why though. They also have a lot of smaller mags for sub-disciplines, although some require credentials as a grad student or researcher. I know I couldn't get a copy of Nature Physics, but was able to get one to Nature Chemistry.
For game design there's Game Developer Magazine, which is run by the same people that do the Gamasutra website. The most interesting part is their "post-mortem" section which is written by the developers of a recent game and has a format of "5 things we did right, 5 things we did wrong." (plus other commentary)
For general game stuff you can get a sub to Game Informer if you sign up for the membership at Gamestop ($15), which will usually pay for itself in discounts if you buy enough used games there. (Edit: Game Informer kind of sucks actually, it's mostly just advertising to hype pre-orders, although some of the editorials are interesting. But since it's pretty much free, why not get a copy)
