One interesting aspect of microtransactions and free-to-play games is that they're ideally suited to charitable initiatives, allowing players to invest their own money via the game towards a good cause.
It's an underused application of this business model, which is normally used for pure profit, but there are a few companies setting a good example. One such company is Grinding Gear Games, the team behind the excellent free-to-play Diablo-like Path of Exile.
Path of Exile launched its first "charity race event" last Saturday, and is continuing to run it until Saturday May 24. So far, the event has already raised "almost $20,000" for the Child's Play charity through sales of a special item called the Angelic Mask. This $5 item is only available during the event, and 100% of the proceeds from its sales go directly to Child's Play. Like the other items available in Path of Exile's microtransaction store, the Angelic Mask is one of Grinding Gear's "ethical microtransactions" designed to allow players to show their support for the game and customize their character without breaking the game balance. It's not a "pay to win" item, in other words.
Path of Exile's Race events are a popular part of the game's online features. They're short-duration events that encourage players to forego playing as their usual character and try something new. The goal is to reach the highest level possible within the time limit, using a brand new character and an empty stash. Players are ranked at the end of the event according to their total experience points, reaching goals, being the first to achieve particular objectives or being the first to obliterate all the monsters in a particular area. Prizes are usually offered as an incentive for players to participate, usually of the in-game variety, but the currently running charity race event also has a number of real-world prizes available for those who progress far enough, ranging from Nvidia graphics cards to Turtle Beach headsets, signed prints of concept art for the game and a private Q&A session on Skype with the developers.
You can find out more about the event and its special rules over on the official site.