Do you join a lot of websites and groups for your crafting?

There are so many Yahoo! Groups and Google groups dedicated to crafting. I've join a couple as a part of my Street Teams, and a few others just for the heck of it and exposure. I didn't realize when I came back to the world of crafting that it would be so vast in outlets for it. Its amazing to see just how many people actually craft. Majority of the groups I've joined have been specifically for card making or scrapbooking. It crazy to see how many people do the same thing you do. Kinda keeps on on my toes, while getting ideas.

What do you think about websites like Squidoo, Flickr, Ning, Yahoo & Google groups?
Is it worth it to join one?
If you are apart of one, do you enjoy it?