Best song for immediate impact when presenting or testing?

I, as most of you, have my regular tunes that I play or listen to when trying out a new system or playing music for friends. My current starter is 'Feels like Rain' by Aaron Neville. It engages me immediately because I love it so, but it is also very well recorded and has a bass voice doing backup which in the right system has a real visceral impact.

I was at an Audio shop recently, listening to my standards, and wanted to show the sales consultant a piece that he might not have heard. I played 'Golden Rust' off the Miles Gurtu album. After about 30 seconds, he pulled out his device and added the song to his favorites. I asked why did he add so quickly, and he said that the opening electronica had a three dimensional stereophonic quality that made a remarkable impression right off the bat. I paraphrase lightly; that was his comment.

What pieces do you play of any genre that have an immediate impact, especially for people listening to a good system for the first time?