Yes, I was part of the Online Writing Workshop for Science Fiction and Fantasy for many years. It is geared towards criticism with the idea of publication like most workshops, but I formed a solid group of friends there, many of whom I'm still in touch with. Some of them have gone on to bigger things in the publishing world and I'm still marginally in touch with some of them. Other of my friends are kind of like me, they really wanted to be published at one point but now they're either doing it for themselves, indie publishing, or not doing it at all anymore.

I actually found that doing the criticism of other people's work taught me more about my own process then having my work criticized. Although the criticism was also valuable because it showed me my blind spots. The most valuable thing of all, though, was forming those friendships.