I have a large music collection and was irritated by the 64GB limitation on my itouch, UNTIL I found Subsonic http://www.subsonic.org. Now my ENTIRE library is available to me via the internet or my phone, with no size limitation! I will repeat NO SIZE LIMITATION, I have heard of people with a TB+ of music using this application. Hands down this is the best software find for me in the last 3 years. If you have an iphone or android you can stream to your phone via 3G from your library off your home computer. I use my iphone to stream to my car stereo flawlessly. Not to mention it sound great.
The most complicated thing about this installation is setting up port forwarding. Which is not to difficult but if you run into problem there are plenty of people on this site that can help you out.
For the recored, I have no affiliation with this company besides being a user. Would love feedback if you end up trying the application. I'm also around most of the time if you need any help setting it up.
BTW, I know this is windows software section but it is also available for Mac, Debian/Ubuntu, Red Hat/Fedora, and a War version.
Edited by zelkea: updated platforms had incorrect info