It's called a design patent. It explicitly covers only the ornamental, non-functional design of the object, and is subject to somewhat different terms than a utility patent.
In terms of IP law, it's actually quite reasonable.
appreciated, however I don't think that people mean "design" as in aesthetic design when they say "invented"
for example, the spinning beach ball is patented... I think we have passed the point where "patented" has anything to do with what people think of as "invention"
In terms of IP law, it's actually quite reasonable.
http://en.wikipedia.org/wiki/Design_patent