Sample product: you can no longer get neodymium magnets from Amazon Shopping. (They were in my Wish List, and then, poof, "This product is no longer available." More searching within the site returned nothing.)
Okay, granted, but that's not exactly what I'd call egregious. They're, um, capable of causing injury, and the kind of thing I would probably want to ensure was only sent to recipients who had a i-know-what-i'm-doing form on file with my legal dept. Not the kind of thing I expect to be available for free 2-day shipping or whatnot.