PopJam
Mixes the ease-of-use of Twitter, with the voting of Digg to find the best funny stuff on the internet. I'm not sure it succeeds, but some of the front page was funny, though it seems to be mostly pictures.
I'm one of the people behind Plancast.com. Our goal is to make it easy for you to share your plans. Maybe you read about us on Techcrunch or ReadWriteWeb?
My Plans: Plancast.com
My Notes: Noopsi.com
My Tweets: Twitter.com
My Code: Github.com