It's a rare thing to have so many influential artists in one place performing at the same time, especially when they are all legends who pioneered the techno genre. 

Kraftwerk, the German techno innovators, played their first show in Detroit in 10 years with a 3D concert at the Masonic Temple. 

At the Kraftwerk After Hours, Kevin Saunderson, Juan Atkins and Derrick May were all slated to perform. That cast by itself is enough to make a techno head drool, but when Kraftwerk surprised guests by performing with Kevin Saunderson... now that is truly a unique and historic occasion. 

(source: Detroit Free Press)