This is also a
stupid way of saying "
off".
Compare...
"I got hit by a car and my head bounced right off of the windscreen!"
...with...
"I got hit by a car and my head bounced right off the windscreen!"
Notice how the word "of" is completely redundant in this type of use.
PS: Sorry to
ryano, as I changed my example since he wrote his
writeup below. This is getting
messy. :)