Ctrl+Alt+Del => Reboots the Colossus Fire Control system in the beginning of the mission, so that they can kill the Iceni and really end that plotline instead of just letting it hang loose waiting for the never-to-be FS3...
It always annoys me to have last look of that goy disappearing into the nebula, trailed by a Shivan ship... and that's it. Better just be killed, swiftly and decisively.
Hmm, what more... let's see:
C+3+Break -> Make every friendly fighter freeze where they are to avoid banging into you, escort ships and other stuff.
C+3+Caps Lock -> Simple - make the wingmen only target Capital ships
C+1+[Support Ship Entry]+Win key => Could you also wash the windows while you're at it?
C+1+[Desired Ship]+Control key => Commandeer the ship in question and use it to do what it's supposed to do.