There is a club near where I live (OK..so its actually a bar, but its got a decent sized dance floor, and some pretty good lighting ) and sometimes a buddy of mine will spin down there with another DJ. The one DJ will play most of the Top 40, Pop, Hip-Hop stuff to keep the people happy, and my friend will play all the Trance, House, Progressive, etc. It is actually pretty interesting to watch them play off of each other. They have been able to come up with some pretty interesting combinations of music to mix together. Its a lot of fun to watch and hear when they are both on their game.