If you have a shofar and want to be part of "the greatest Shofar-blowing event since Sinai" mark September 18 on your calendar. Art Kibbutz NYC is organizing shofar-blowing flash mobs as part of the build-up to Rosh HaShanah at the end of the month. Right now flash mob locations are centered in the NY area, but surely more cities will join the fun as word spreads.
The shofar (שופר) is a Jewish instrument that makes a trumpet-like sound. In ancient times shofarot (plural of shofar) were used for many reasons, including announcing the start of a new month, the beginning of festival holidays and the commencement of battle. You can learn more about shofarot in "What Is a Shofar?" and more about ritual shofar sounds in "Sounds of the Shofar."
What is a flash mob, you wonder? A flash mob is a group of people who suddenly assemble in public places to perform organized routines or specific actions before dispersing into the crowd. A flash mob could do something as simple as freezing in place at Grand Central station or performing a choreographed routine to "Do Re Mi" from The Sound of Music. (You have to watch the "Do Re Mi" flash mob, it's guaranteed smile material.)
For more info about shofar flash mobs on September 18 visit Elul Shofar FlashMob.