I've seen this feature on another online game where you would be able to play your own music inside your house or on a lot you own. Basically what I'm suggesting is a section on the stereo that would say "Custom playlist" and when you click on it, there would pop-up a window where players would be able to add their own songs via direct links to the mp3 song (example: http://host.net/song.mp3), naming and including them in a playlist. This playlist would remain saved and ready to listen to next time. (you can get direct links to songs from pages like mp3skull) Everyone on the current lot could hear the songs. Only controllable by lot owner & roommates. I don't know if it's possible to make this work with the Sims but I just wanted to suggest this one because parties and generally gathering up with friends on a lot/jamming/pizza making/working on skills together would be much more fun.