treasuremytext is a free British service that allows you to save text messages from your phone to the web on an anonymous, communal log, or “slog.” Recent messages appear in a column on the main site where they can be read by all and sundry, subscribed to by feed, and even loaded onto an iPod as plain text files. jill/txt has a transcript from about two weeks back:

trying to convince myself that there was nothing there but i still find myself thinking about you
night nimet . . . . i miss you
How about sorting that taxi out for next week? For real?
Ok smart arse when you are there then! And then i will fix your issues for you, all of them!
U have beautifull eyes
Dont ring ill b down bout halfpast babes
Me to hes just arrived txt u l8r baby
Nite nite xxx
Nite nite fat sexy bum.Txt u tomoz nite nite xxxx

Not exactly prize-winning stuff, but has a nice dreamy flow of chatter plucked out of the air. Reminds me a bit of a game I played in elementary school where you go around a circle and improvise a story in broken-off pieces. Reading the site today, the entries seem to have taken on a smuttier tone. And a good number aren’t in English. But an intriguing experiment nonetheless.
But it would be more interesting if the logs had some focus. Something like the City Chromosomes project, which is building a networked chronicle of the city of Antwerp, all by SMS.