foursquare

its pretty fun.
all you have to do is own a smart phone ie: blackberry, iphone(i am pretty sure you can play it on iphone), droid, any smart phone with gps capability.
join and check into all the places you go. minus the place you work.
upload a photo and you get mayorships, a lot of places you are a mayor you get discounts/ freebies with them. its lame but fun. do it.