With online gaming as huge as it is in Korea, no wonder the Korea National Tax Service has just started virtual taxation. Basically, virtual asset transactions get a value-add tax. Here's the kicker: the actual items and currencies don't belong to the gamer but to the game's publisher. Site im69.com lays out the policy:

Sellers who do between 6 and 12 million won/half year in business will have VAT auto applied by transaction's middle-man
Sellers who do more than 12 million won/half year in business will need a business license and will pay the tax by themselves

According to a National Tax Service official, "NTS would be able to track all transactions for taxation of virtual items." Your move, IRS.
Virtual Taxing [im69.com via Game|Life]