ZumoCast

ZumoCast turns your PC into a kind of media server, giving it the ability to stream music, video, and files to any other PC - or even to your iPhone, iPod Touch or iPad. (Android support is coming soon.) It neatly overcomes a major problem for mobile devices: limited storage space.
 * ZumoCast **

After installing developer Zecter's ZumoCast client on your PC (it's available for Macs, as well) and creating an account, choose the items you want to make available. By default the software pulls from:- Windows' Documents, Pictures, Music, and Video folders, but you can just as easily add any other folders. As long as you leave the PC running, you will be able to access that media elsewhere. You can listen to music on your work PC, play videos on your iPhone, grab documents on your iPad, and so on. The free ZumoCast app even lets you download selected files to your device.

ZumoCast is perfect for storage-strapped devices, or for any PC that doesn't have all the media housed on your other computer.