Up to 30% spend money on World of Tanks

At least 25%-30% of players on World of Tanks have spent real money on in-game items for the free-to-play MMO, developer Wargaming.net has said.

Company CEO Victor Kislyi told Edge in a GDC interview conversation was possibly "the highest in the industry".

"Like Zynga, in many respects, we've created a new sector," he said. "Those fat, beer-bellied, bald older guys - they want to have fun without paying $50 for a box, which they'd never do and probably never did."

422,000 users are signed on to World of Tanks currently, with a quarter of that number coming from Russia. 13,000 sign up to play everyday.