Today i will be going over some of hidden features of the property actuator
The property value syntax is not really hidden. It is just not documented in the wiki :D.
I didn’t know that you can do this (neither the things you make in the tuto about align dynamic objects to a surface with constraint actuator). Thanks! 
one thing I would really like,
if property is string----trigger
if property is valid gameObject--------trigger
if property is not string------------trigger
if property is Vector--------trigger
if property is list
this could be very handy for AI and many other applications.
(Mutating a property could define a behaviour)
like if property is Vector-------(add object at vector and set target as object)
if property is valid game object----(steer to target)
Monster True but lots of people don’t know that you can do it