I'm sure I'm not the first one to do this, but I had the run of the house several weeks ago and happened to be stupid-high. One starts playing an MP3 in WinAmp and half a second or so later, one starts a YouTube video of the song so that they are just start to go out of phase and it sounds like the band is performing in a football stadium. The game is to see how quickly you can hit the sweet spot.

E6's Synthesizer works especially well:



(you'll have to find the MP3 yourself.)