Actually, it's referred to in Windows Vista as Auto-hide the taskbar. Why would you want to hide the Taskbar? In today's age with larger, wide screen monitors it seems unlikely anybody would be fighting for more screen space to necessitate the hiding of their Taskbar. Even if you hide your Taskbar it can still be easily found. First of all to hide your Taskbar right click a blank area on your Taskbar, click Properties and on the Taskbar Tab check the box "Auto-hide the taskbar" and click ok. Yes, your Taskbar disappears, but if you want to bring it back up again, temporarily that is, then simply hover your mouse down to the bottom of your screen and it will pop-up.

Purchase the training video and you can see this in action for yourself!