It's getting close to the spooky holiday again, and Gamepro has this amusing article
posted with various ideas for game-themed halloween costumes. They list various licensed and home-made options for each costume, along with price range for each. It's a good starter guide but as always there's plenty of room for personalized innovation. I particularly like the gaming hardware costumes--is that Jeremy dressed up as the NBA Jam cabinet?
Me and my brother have been threatening to make Mario and Luigi costumes for years, as they're pretty cheap to do and we kind of look like the brothers Mario already. While my girlfriend has done medieval costuming for renaissance guild performances for years, she said the only way she's ever dressing as Princess Peach and/or wearing anything pink at all is if Scott and I don the caps and overalls and share in the Mushroom Kingdom facebook embarrassment.
Scott also had a pretty good Link outfit a few years back that he made out of green medical scrubs, complete with a blue plastic ocarina. I've seen some insanely accurate Link outfits at cons and trade shows over the years so that's definitely one that can get expensive, especially if you want real chainmail a really good sword and shield.
Back in college I managed a halfway decent Big Boss/MGS3 Snake costume for a halloween party with just some cheap 'Nam era camo, a bandanna and an eye patch. Most gaming costumes have to be home-made because the games they're based on aren't mainstream enough for commercial costumes, but with $600 Mjolnir Spartan armor the official stuff can get just as pricey. Still, if you're thrifty and have some skill it doesn't take a lot of cash to make a really good gaming costume. Remember, the best ones are the most obscure; why buy a Hot Topic licensed Zelda costume when you could be Tron Bonne or freaking SHODAN