Im building a portable jukebox. Here is what I have so far:
(http://www.fordmanf150.com/etouch/newjukebox.jpg)
more pics and build details to come.
Fordman
In reality all you need is a decent disco PA system an all in one touchscreen PC and big USB hard drive for the media. I actually DJ'd a put with mine when they asked me at the last minute, i just hooked it up to my PA amp and speakers on some speaker stands with my mixing desk and a mic. I don't have any PA gear anymore as moving it around and storing it was a PITA but it was good times. There are far more friendly features in there for DJ'ing now like the announcements and the ability to have the queue always shown.
Same with me...I Dj'd for 7+ years, only just got rid of gear - and it's still in the family! Kept my PC full of music, irreplaceable!