I know it may be ludicrous, but I guess I have a tendency to stare at people's toes. They can tell so much about the person. Are they well groomed? Do they work a lot? Do they have free time? Do they have kids? And the list can perpetuate for miles.
And the bigger thing is is that no one person's toes are homogeneous to another's. They [the toes] vary from person to person, from time to time. Police officers and detectives use fingerprints to find the culprit since everyone has a unique imprint. I say, toes could work as well.