Making it easy for people to have meet up

Human is social animal. Many activities we are involved in requires many people. The founder of MeetUp.com makes it easy for people to setup meetings and notify people who are interested. Their moto is "Whatever your interest. Wherever you are." People who have similar interest can find and setup meetings locally. There are thousands of meetings every place across united states. People meet up for hiking, vollyball, photography, investing, and alot more. It's making millions.

Problem: It is difficult to find people with similar interest locally.
Idea/Solution: Website + Interest + Location + Free + email notification + easy to setup + easy to participate
Site: http://www.meetup.com/