I run the game in fullscreen mode and most of my sims are large landscapes, so the 1 pixel Combat Mech is a good size for my purposes.
Press "x" to use the weapon (defaults to bomb, change with ctype) and press "c" to activate the shields.
If you tap "c" while moving (with the arrow keys), it looks pretty cool.
Only tested with Jacob1's (totally awesome) mod.
Here's the script, in case anyone is interested:
Ohhh, okay XD
There we go.