There is a plethora of websites which allow creators to 'borrow' assets to implement in-game. The model of granting access and permission to use these assets differs across websites and may range from an upfront payment to a portion of profits (if the assets are used commercially). This is not an issue with large video game publishers (such as EA, Activision, or Sony), but when these self-contained companies create large and detailed worlds, most of the assets they create end up being used only once.