I can! I learned in Feb of THIS year, lol, yeah, that's how big of a deal it was to me, I fucking remember when I learned it. And I don't smoke cigarettes, so yeah, I do it with bud smoke. As long as you have enough smoke it's fine...I mean, I've never even done it with cigarettes....
Practically everyone I know can do it, and it bugged me that I couldn't. So one day I sat down with my bag and my pipe and I kept taking hits and trying to blow rings until I managed it. By the time I did one, I was SO fucking HIGH, lol, I almost didn't realize I had done it. I tripped a little....