I'm in Alpha Xi Delta sorority and Phi Sigma Pi National Honor Fraternity. Both of these org's are important to me and that's why they're both in my sig!
Since I don't think a lot of GreekChat people know what PSP is -- we're coed with chapters all over the country. Yeah, we're an honor fraternity but we're also big on brotherhood with socials, big/little brothers, just hanging out with each other, and all that stuff. It's a bit like a fraternity/sorority for geeks. (Yep, I'm a geek.

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There's another girl at my chapter who's in AXiD and PSP, which I think is cool -- she's my brother AND my sister!