RuneScape. According to developer Jagex, a pair of RuneScape players recently took advantage of their game's Bond system (akin to PLEX or CREDD) to fund their trip to the RuneFest fan convention in October. The studio detailed other positive effects of the Bond system in a press release this morning, explaining that the system has improved the game's economy:
Since their September 2013 debut, around 2.3 million Bonds have been purchased; more than 80 percent of those Bonds have been redeemed for membership, with 27.6 million membership days obtained to date. The introduction of Bonds also had a swift and dramatic effect on the levels of gold-farming in the game, which plummeted by 81 percent within weeks, and also helped bring a more stable in-game economy for players. Over the past year, more than 316.5 billion in-game gold pieces have been sunk into Bond trades by the community.RuneScape VP Phil Mansell said that over the last year, "nearly 20% of RuneScape players [paid] for their membership subscription through their in-game efforts and half of the premium RuneCoin currency comes from bond redemptions."
[Source: Jagex press release]