I mentioned HabitRPG in a previous Wednesday night meeting. It's a "gamified" to-do list. I've been using it for everything from remembering to drink more water to getting specific tasks done on my game. It's been one of the best, most consistent motivators that I've ever found for encouraging good habits and discouraging bad. The mobile interface is a bit wonky, but they're working on it. The web interface is really the best way to manage it. I recommend the mobile mostly for logging completed tasks.
One nice feature of the game is the wide community of others working on tasks. You can join parties and guilds, and work together with others to complete quests and challenges.
This is the Diablo clone with giant skill web that I mentioned. Here's a link to the interactive skill web: http://www.pathofexile.com/passive-skill-tree
Description from page: "Path of Exile is an online Action RPG set in the dark fantasy world of Wraeclast. We're a small independent team of hardcore gamers based in New Zealand and have created Path of Exile as the game that we'd want to play ourselves."
This is pretty a pretty quirky use of digital maps. A guy in the UK created a map service that divides the world into 3-meter squares and gives each square a 3-word tag. It's much easier to remember than numerical GPS coordinates. Could this be used as a name/clue key in a real-world city game?