I'm a sucker for great design for it's own sake. If a great design helps to sell products then even better. Most of the time it does.
It's part of the intagible bit of marketing that most of the public think they can't see because they're "not designers or artists". The thing about great design and art is that the man/woman on the street instinctivley knows good design, they just never trained themselves how to recognise it or describe it.
This is a great site I've just found which has some of the best product and packaging design I've ever seen. The examples are clear and work wonderfully, enjoy.