Textastrophe's tag line explains the Tumblr in a nutshell: "Next time you post your phone number in a public place, think again. This is a collection of text messages I've exchanged with people who have done just that." Basically, it's a hilarious series of text conversations trolling people who leave public messages on Craigslist and elsewhere. It's like one of my favorite discontinued Comedy Central shows, Crank Yankers, except with text messages.
Hilarity, of course, ensues. Check it out: