The idea of tying online games into the real world isn't completely new, but there were two companies at TechCrunch50 with interesting spins on the concept.
First, Akoha. It's the card swapping game "Magic" with an evangellical twist. The cards are do-good tasks. Plant a tree. Read this good book. Smile at a stranger. You do the task, go online and tell the story of doing it, and then pass the card along to someone else.
For each individual card you get, you can see the path it took around the world (assuming people tell their stories online), gain points, meet people, and so on.
It's a clever viral marketing concept applied to good works. Users can create and publish their own cards, and one of the panel judges noted that it could be contaminated by commercial interests: "Buy someone a Starbucks coffee!" Presenter Austin Hill said the team will monitor the cards, but that one idea is, in fact, to encourage charity and investing in good companies, so a legal card might be, "Replace a lightbulb with a CFL," sponsored by GE, providing GE has some sort of charitable contribution tied to their involvement with the program.
If you want to explore the world from the comfort of your den and avoid doing anything good, there's the new gaming platform Playce. The company is building out "mirror world" sandboxes that game developers can program social games into. The textures and graphics are pretty good considering that the games run in-browser (IE only, so far), although evidence of any kind of real-world physics were missing from the demo.
The idea is that you invite your friends into games (you can import your social graph, using OpenSocial) and then, like, blow up your home town together. Fun? We'll wait for the games.