When your best friend breaks his arm, you sign his cast. When the nicest rock star in the world falls off a stage two songs into a concert in Sweden, breaks his leg and then still finishes the show, you need to get more creative.

Fans can now sign Dave Grohl's "virtual" cast by tweeting well wishes at the micro-site SignDavesCast. About 300 of them will even be printed on a flexible cast sleeve that will be presented to Grohl as he recovers after having surgery on the leg earlier this week.

The idea came from the creative agency EVB and development company BausCode. "The internet is best when it's used for good," said a representative for EVB said in a statement. "Commemorating such a hardcore act as finishing a show with a broken leg felt like just the thing to do with the technology."

Foo Fighters had to cancel the remaining dates of their U.K. and European tour including a headlining spot at this month's Glastonbury Festival. British favorites Florence + the Machine have since taken the Foos' spot at the event.

Grohl apologized to fans for the cancelations in a lengthy statement and said he's only following doctors' orders to "lay low" for a while. "We’re doing our best right now to work out a plan, so bear with us," he wrote. "You know we’re good for our word. But for now, I need to make sure we have years of gigs ahead of us."

Check out video of the fall below.

Dave Grohl Breaks His Leg During a Concert in Sweden