From Dave Winer, behold the Twittergram!
by Russell Shaw
Dave Winer, who is generally credited with inventing the RSS (Really Simple Syndication) standard that makes blogging possible, was lamenting on his Scripting News blog that although Twitter is so cool, its text-based, 140-character limit makes it impossible to embellish Twitter messages with multimedia.
Oh, but then, Dave worked up something called a Twittergram. Link to a spawning .mp3 file within a Twitter message.
Net result: kind of Twitter message meets Podcast.
You can see what I am talking about here.
“If you want to play the game, record a response, no more than 200K, upload it somewhere, and link to it from your Twitter account, and put @davewiner somewhere in the text of the twit (so I will see it),” Dave writes. “Of course I’ll be surprised if anyone actually responds, but what the heck, maybe people will.”
Well, I did 
