Toastmasters has been my best way thus far to make friends in Beijing.  However, table tennis is my second-best outlet.

I played at a local table tennis club last week, strutted my stuff, and was invited to come back again.  After winning a few matches this week, I got to know some of the player a little better. 



From talking to my pingpangqiu (ping pong/table tennis) friends and others, most Chinese are on QQ.com messenger.  QQ only recently came out with an English version, so people are shocked when they hear that I have QQ.  If they speak English, or interact with foreigners at all, they probably also have MSN/Windows Live Messenger (but they still prefer QQ).  QQ is very important if you want to correspond with true Chinese,  maybe more important than email, phone, or text messaging (SMS).  This way you can interact with them throughout the day.

In fact, you can talk to people very easily on QQ, even if they don't speak English!  I use http://translate.google.com to translate Chinese characters into English, and vice versa.  There are some really nice people that I have met that simply don't speak English, so I make it easy on them.