Hi ppl, as ruben01 with his Dude, that’s my bullet I did a game for Ludum Dare 18 Jam, Grappling Hookus.
The idea is very simple, grab enemies with right mouse button, throw them to other enemies with left mouse button.
Here is a screenshot:
http://img824.imageshack.us/img824/1125/2034shot0.png
and a superlink, like notch did in his metagun post:
Hope you like it.
It is a nice game but sometimes I don’t really know which car is going to shoot.
About which track is going to shoot, it is always the nearest free to do the action. I mean, if you want to grab an enemy it will use the nearest truck with no enemies grabbed, and if you want to shoot an enemy it will use the nearest truck with an enemy grabbed (already over the truck).
About knowing if you have an enemy grabbed or not, that is confusing because the enemies are almost transparent so you can’t know if you have one or not 
that is because I suck as an artist.