I'm late to the Twitter game but still find this interesting.
Dave Winer has decided to bring voicemail to the internet, soon to be tied into the popular microblogging service. What he calls a TwitterGram will send a tweet with an URL to a 200K audio file. Good for the twittering while driving, updates that require more than 160 characters, sharing a song (at a concert), etc...
His rationale is that Twitter is to a blog what a TwitterGram is to podcasting.
A web-service should be up shortly at twittergram.com. I expect that it will gain traction but shouldn't come ...