Play songs from iPhone through computer.

A major annoying problem I've had with my iPhone has been playing music at home, on the train and while at work. I've always felt hatred towards the device for it not letting me just drag and drop my music where I want to. For quite some time now I've had a music library at home, which was synced to my iPhone and then another library at work. This sucked as they where never in sync and I always wanted a song which was at home while I was at work or vice versa.

Today my life was changed.
I no longer have two music libraries, just the one and I now play the songs directly from my iPhone through my computer via iTunes.

Plug iPhone into any computer with iTunes.
Select your iPhone under Devices.
Select Music under your device.
Play songs as you normally would.

Up until today I never knew this was possible but it was a massive oversight on my behalf and is a great solution to a problem I was having. It also has a plus side as it syncs your ratings, play counts, etc.

But it really was quite simple -.-