We pick our favorite features from the upcoming Lion OS X for the Mac
3) Auto Save + Versions
With Auto Save, your Mac automatically saves what you’re working on so you don’t have to. it’s an improvement for anyone who’s ever lost hours of hard work after forgetting to press Command-S. Versions is a new feature that charts the history of your documents, taking snapshots in time, and displaying them side by side with the latest versions in an easily browsable timeline. You can review the past iterations of your compositions, restore a previous version, or copy and paste from old versions to new ones.