For physical there is the "Hacker Dojo" in Silicon Valley and maybe other places. Open space you can go and work on projects, and find others to collaborate with.
Virtually there are ones everywhere, any open source projects. Look on GitHub.
At the workplace you can engadge in various "eXtreme Programming" type activities.
Personally, other than getting a little reved up by meeting people at conferences, talks and such I don't like this kind of programming. Done it for too long, nowadays I just want to work on my own stuff at my own pace. But that's just me.