The iPhone, iPod touch and iPad all make great music players. You can sync music to them from your computer as well as download music directly from the iTunes store. You can now even stream music from your iTunes collection via iCloud/iTunes Match. While this is all great for getting music into the devices and listening to it, there really isn't a built-in way of getting music out of the devices. This is where Song2Email comes in. While I certainly don't advocate stealing or sharing music illegally, there are times where you may want to get a song from your iDevice to another system and you don't have access your iTunes library. 

Song2Email let's you email songs from your iDevice

Song2Email performs the basic task of letting you choose any of you songs and email them to any email address you want. You can choose one song or multiples songs and email them via WiFi or 3G (20 MB Limit). The App is Universal so it works on iPad, iPhone and iPod touch. This is one of those Apps that has a simple function and it does it very well. I wish that there was more that I could go on and on about, but there isn't. It works!

You can get Song2Email for $0.99 here from the iTunes