Expat social groups in Medellin

During the time I lived in Manizales, I was part of a group that met for coffee and BS a couple times a week.  The group was a mix of Colombians and Americans.  I really enjoyed it. The excuse for meeting was for the native Spanish speakers to practice english, but it was much more than that.  I made good friends, both american and colombian.

Now I live in Medellin and I wonder if there are any similar social groups, clubs, or special interest expat groups (ie: cycling, hiking, reading/book review, etc) or places where expats hang out for coffee or meals. 

I live in Alta Calasanz, and I am looking for social contact and good old coffee and chisme sessions.

any suggestions would be appreciated