Physics Animations (Image heavy!)

I’ve been messing about in the GE recently, mainly dropping enormous, heavy red balls into brick walls. Anyway, here are a number of images and an animation…
House:
http://dominomf.com/smcfiles/Z-Axis_Smashing.jpg
0001_0413 compressed.avi - The animation, roughly 5 MB

5 row block:
http://dominomf.com/smcfiles/Z-Axis_Smashing%20II.jpg
http://dominomf.com/smcfiles/Z-Axis_Smashing%20III.jpg
http://dominomf.com/smcfiles/Z-Axis_Smashing%20IIII.jpg
http://dominomf.com/smcfiles/Z-Axis_Smashing%20V.jpg

After seeing the chaos this caused, I decided to find out just how many rows would stop the thing. So…

20 row triangular prism:
http://dominomf.com/smcfiles/Z-Axis_Smashing%20VI.jpg
http://dominomf.com/smcfiles/Z-Axis_Smashing%20VII.jpg
http://dominomf.com/smcfiles/Z-Axis_Smashing%20VIII.jpg
http://dominomf.com/smcfiles/Z-Axis_Smashing%20IX.jpg
http://dominomf.com/smcfiles/Z-Axis_Smashing%20X.jpg
http://dominomf.com/smcfiles/Z-Axis_Smashing%20XI.jpg

Explosion:
For a 30-minute Speed Modelling Contest (http://blenderartists.org/forum/showthread.php?t=82195) I made this:
http://dominomf.com/smcfiles/Z-Axis_Explosion.jpg
Blend file: Explosion.blend

Tower
http://dominomf.com/smcfiles/Z-Axis_Smashing%20tower.png
0001_0170.avi

Awesome: how do you bake the Physics?

In the top Blender menubar, Game > Game Physics to IPO. :slight_smile:

Thanks a million!

Well, for my next one I wanted to have a trapdoor involved, but I can’t for the life of me work out how to use the hinge constraint thing. I’ve looked at the file, copied and pasted the python, added everything there was AFAICT yet nonetheless it doesn’t work.
Please can someone explain just how you go about setting up a hinge?