Social groups and fraternal like organizations after college, any ideas?

[Indian Race Troll (IRT)]

Like Estate, I too have thought about getting a social life where I can make more friends. In college, I did not rush a fraternity which did hurt me in regards to getting laid and having a good social experience. My university was dominated by the Greek Life scene, you couldn't even get a job at some of the places like bars and clubs unless you were involved with Greek Life. I have made friends from the gym and the bars but I have never really had the feeling of belonging to a group of people that was almost like a brotherhood. Now I have heard of the Free Masons but I want to start doing some research on what kind of organizations after college are like a fraternity or something of the sort where you can form a brotherhood with real men. Would love some suggestions and ideas.

Also starting my masters soon but I am sure they don't let grad students rush fraternities.