In my limited number of plays in games with shaker motors, I have found a very wide variation in how shaker motors are used.
I found Transformers to have excellent and varying shaker motor usage that enhances immersion. For example, the Megatron lock sound perfectly meshes with the slowing rumble of the shaker motor. It is subtle and effective.
I found Star Trek less creative. Perhaps I was playing old code, but rumble effects seemed limited to a mild rumble with ramp shots and a full-on anxiety attack when the Vengeance is destroyed. It "works" but can feel monotonous and ham fisted after a while.
What do you find as particularly memorable uses of shaker motors or particularly unimpressive applications of shaker motors?