I searched the site before posting this and didn't find that anybody else had done so- hope it's not redundant!
Here's a link to a fun "game" developed by the University of Bath, England.
It's on the "Bailey of Bristol Caravan Stability" site.
It lets you load a trailer and then tells you how well you did in terms of stability.
Armchair roadtesting- I love it!
I actually had the most fun finding out what happens- scientifically speaking- when I loaded the trailer badly
The whole site's pretty interesting if you like the "dry science" approach...
Here's the link to the game Bailey of Bristol - Caravan Stability Studies
I think you have to have the Adobe plug-in to play...