How can I change Unity's super-t binding to something else?

In the Compiz Config open the Unity Plugin page, change the "Key to show the launcher" to anything other than just Super. Mine is Alt+Super.

This will alter all Unity shortcuts. So opening the first program in your launcher is no longer Super+1 but Alt+Super+1.

They should really have a configuration panel for Unity shortcuts.

This isn't a real answer to the question but another approach in unity manner.

If you use it often consider putting it into the unity launcher. Just search for "terminal" and then drag the icon to the left side pane. You can then start it with Super-[number].

Just in case you're interested: I want to know the real answer too!

My muscle memory is also programmed to use Super+t for open terminal, so I decided to make a ppa for this: https://launchpad.net/~hansvschoot/+archive/ubuntu/unity7. It contains the unity 7.2 branch at the moment (which is used in 14.04) with line 56 of the launcher/TrashLauncherIcon.cpp commented out to remove the shortcut.

So if you are running ubuntu 14.04 you can run the following commands to add the ppa and install the modified unity:

sudo apt-add-repository ppa:hansvschoot/unity7
sudo apt-get update
sudo apt-get install unity

afterwards you can simply use the shortcuts tab under keyboard settings to assign Super+t to open a terminal