Blizzard has had unprecedented success with virtual item sales on the release of the Celestial Steed – a special in-game mount for World of Warcraft that costs the princely sum of $25, €20 or £17.

According to WOW.com (via GamesIndustry.biz), a seven-hour queue of 140,000 people had formed within three hours of the mount’s release last week.

That already represented revenue of $3.5 million – or more than a million dollars an hour – on sales of what is, essentially, just an art asset for the subscription game. The translucent flying horse leaves trails of stardust behind it as it gallops across the sky.