I was surprised (and a little annoyed) to find that while the vast majority of the shredding in our office is done in front where snail mail is scanned, etc, it is in the back office where we have burned out shredders. My office manager proudly showed me the can of "shredder oil" that they run into the machine on occasion. (I would have asked why she was not sharing this tidbit with us in back, but I doubted I would have liked the answer).
A little oil is a good thing. so far a few hundred bucks from staples works good enough, but I would like one to sit on top of a trash compacter!.