S2Games, the creaters behind Heroes of Newerth, today announced that their DotA game will be removing its purchase cost, which was $30, and will now be completely free to play. Heroes of Newerth did not require a subscription and was supported by a combination of an in-game item store and initial game purchase. It seem S2Games figured out it could get a lot more people playing if they just removed the game cost, which in turn should get more people buying items from their game store.
Players who purchased the game will now become Legacy members and receive special bonuses such as having complete access to all heroes as well as any content update, not including expansions. Free-to-play players will have to purchase heroes, if they want access, as well as new content.
You can read through the F2P FAQ over at the official HoN site.