I just installed the latest LTS release of Ubuntu in a friend laptop. But here's the issue: He has a 15'' screen and the Unity Dash takes quite a chunk of the screen! Combined with the upperbar he doesn't have a lot of screen space left for web browsing.

My question is: Can me make the dash fade away while we open a browser window? I know that Cairo-dock (which I use on Xubuntu) does that, it disappears when the firefox window is open and appear only when the mouse pointer gets on it. Can we make the dash behave like that? My friend likes the dash and he doesn't want to get rid of it but he wants to save some screen space on the internet.

If not fading, perhaps it could be shrink?