Nokia Nseries DJ Mixer - Be Your Own DJ
According to a tip (thanks Anthony) and a search result that landed me on Symbian-Freak, I found that Nokia Nseries in India has this cool app available for their Music Edition Nseries devices called DJ Mixer.
DJ Mixer has 2 functions, mixer and karaoke. With DJ Mixer you can create your own playlists or load an existing playlist from within the the music files on your device. The only problem that I found with this is that it will only add MP3's that you have stored. If you've converted your music to AAC format using Nokia's Music Manager you won't be able to find your music. Once your playlist is created you can listen to the playlist and mix the styles as you like. Lol, I'm not a DJ so I have no styles!
You can load your own MP3 from your device and record and save your own karaoke tune. Unfortunately I got a java error when trying to listen to what I recorded... maybe that was a way of saving me from myself, lol.
All in all the app seems kind of fun, and paired with some stereo bluetooth headsets you could really have some fun.
Visit NseriesIndia for more info, but the download on the site is only for consumers in that region. On the site it states that Nseries DJ Mixer is available for the N70ME, N91 and N73ME but I've been playing with it on my N95.