there are several options.
kebab shop trainees tend to look at them constantly so as to know how not to pack a kebab before offering it up for sale,to being sold as earmuffs from your high street retailer.
some have been photographed so that medical students can see what a rottweiler suffering from rabies looks like.
access to them can mostly depend on how much cash you have before of after consuming copious amounts of alcohol.
no doubt dd or others more informed on the subject may choose to enlighten you further. 