Be careful what you twit for, because your 140 characters could land you in the slammer. Just ask Elliot Madison.

Madison, a 41-year old self-described anarchist, attended the recent G-20 protests in Pittsburgh and, like a good 21st century rabble-rouser, used Twitter to direct his comrades around the mayhem.

Coppers didn't like that so much, so now they've arrested him for hindering apprehension or prosecution, criminal use of a communication facility and possession of instruments of crime, which we can only imagine means the police radio found in hit Pittsburgh hotel room, and not Twitter, which is everyone's.

Investigators are taking this thing super seriously: they raided Madison's Queens apartment and removed antiquated items, like "newspapers," an "address book," whatever that is, and a picture of Lenin. Anarchists are so predictable.

Send an email to Andrew Belonsky, the author of this post, at andrew.belonsky@gmail.com.