The humble sidewalk chalkboard—it's not the most heralded of advertising media. But Synergy Fitness Club in Jersey City, N.J., has elevated its chalkboard musings to an art form. For several years now, Joe D'Allegro—a freelance writer and comedy-show producer, who works part time at the gym—has been writing witty, topical and flat-out hilarious musings on the board for the amusement and edification of passersby, and secured some pretty good press for the business in the process. Check out a bunch of the messages after the jump—and the whole gallery on Flickr. (D'Allegro has not yet used the hoary 24 Hour Fitness line about an alien invasion: "Whey they come, they'll eat the fat ones first." But he probably wouldn't be opposed.) There's also, for the Tumblr-ly inclined, a site called The Oracle of Synergy, updated with all the latest ads. Via Laughing Squid. UPDATE: D'Allegro emails us to say, "I am now a part-time junior copywriter at Warehouse Agency, a freelance writer, and produce comedy shows on the side. I will try to put in something about aliens eating the fat ones first. I've never had an alien-themed board, so it'll be fun."