YELP.

Ever heard of Yelp? It's a fantastic site for writing reviews of restaurants, stores, services, and anything. Not only do you write reviews, but you can check into places on your smartphone for cool deals (think: free food), connect with others, and attend sweet Yelp events. I've been part of the site for about five years now but only really got into it within the past year and half. The events are fantastic, the people awesome, and I always leave with a big smile on my face (and occasionally, a balloon).