Valve has added a new feature to the Steam Store, in the form of game-specific "item stores."

Item stores will allow developers to sell in-game items such as weapons and clothing for a set fee.

This is in addition to community markets, where players set their own trading price for items.

The item store for Rust, currently the only one active, lists many of the same items as its community market, but often at a lower price.

A feature like this offers developers a standardised system through which to run microtransactions - and an extra revenue stream for Valve.

Introduced without fanfare, it will be intriguing to see where item stores go.