Hi there. I help organize the Beer && Code events, and ours is definitely a great way to a) meet like-minded programmers b) make time to learn a new language or hack on a side project.
We do see some collaboration happening at Beer && Code, and I wish there were more. The best way to get in on a side project is to go to the events and meet people. If they seem cool and you find your styles are similar, find out what they're hacking on and fork it if it is on GitHub.
To get you started, feel free to hack on any of my projects at https://github.com/TheDahv. I like collaboration and I feel like I learn more from it.
Finally, in case there is any confusion, Beer && Code meets in both Cap Hill and in SLU on an alternating, every other week basis. Tonight's is in SLU and it would be a great opportunity to experience the entrepreneurial vibe going on there.
Hope that helps!