In a past post (el emigrante) I brought folk's attention to some free online video games which dealt with "Grenada-esque" themes but were done in very questionable taste. As a contrast, Darfur is Dying is an online "game" which actually tries to spread some awareness about the situation in Darfur and is done in a much more respectful and realistic tone. It is still basically a video game so it definitely has its limitations as a way of conveying information. I also wonder to what extent it might be considered a form of propaganda.
I've noticed other examples of people using online games to encourage people to think in certain ways about a certain situation. The most fun example which comes to mind is the McDonald's Videogame where you are given the task of successfully running McDonald's. The action takes place on four different levels: initial production of feed and livestock, preparing cattle for slaughter, management of employees at the franchise-level, and finally setting the broader corporate policies. The game has a very good cartoon visual-style and is simple enough to be manageable, but complex enough to remain interesting. The game also has an interesting anti-McDonald's slant; opportunites abound to engage in all sorts of shady activities (e.g. adding industrial waste or hormones to the feed, mistreating your employees, bribing a variety of public officials, bulldozing a tribal village for their land, etc.) and the economic and ecological harms which McDonald's contributes to are emphasized throughout.
I suspect that the McDonald's game has actually gotten some people nervous because I've recently seen a hastily programed game called Bacteria Salad which emphasizes the dangers of fuits and vegetables?!?!?