In downtown San Francisco today, several office buildings (at least four around Second and Jesse) conversed with each other, as they do, with Post-it notes. And it's downright delightful. They even played hangman with each other. Behold:

Stuart the Minion approves of the newest social network in SF #sfpostit pic.twitter.com/ZyCx6uV791 — Kevin Stapp (@redstappster) April 4, 2014

There's my @postitproducts! All week the bareMinerals office has been posting to neighbors. Started w hi #sfpostit pic.twitter.com/nHxPR3AWL0 — Aly (@alykate) April 4, 2014

Post-it Party at Dada Bar (86 2nd) at 5pm, folks!