Computer meltdown? No backup? Well, at least your tunes are safe. Google Music just gained a new feature that lets you to download your entire library including purchased songs. A simple click in the Music Manager is all it takes to restore your entire collection -- or just your purchased music -- from the cloud . In addition, the web interface now allows you to select and copy multiple tracks to your device of choice. While there are no limitations when using the Music Manager, purchased items are restricted to two downloads each via the web interface. So next time your system crashes go right ahead -- rev up that broadband and fill up those hard drives