Do you have all you music on your home computer or iPod but want to play it at work? Download Simplify Media (it's free) and you can share your iTunes library across all your platforms (PC, Mac, or Linux) and anywhere you regularly go online. Even if you work in an environment with firewalls, this program will allow you access (it is small and contains no dangerous virus or spyware). The founders came from a Silicon Valley company that specializes in secure email and online file sharing; all this means to you is that they know what is safe and how to get around barriers (except if you work at a bank or hospital, both of which use high security firewalls). Coming from the biz, they also know what is legal; you only have streaming access to music, you can not download it.
The best part is that you can share music libraries with 30 of your friends (all for free) and visa versa. And if you are not using iTunes (why not?), the software is also compatible with Winamp and even Linux protocols. They even offer an iPhone app that works with either WiFi or 3G connections, so you can listen to your music on your phone from your home computer as you sit waiting for your delayed flight or train.
Let your music soothe your soul no matter where you are.