Walking Dead Season 1 Episode 1

In the very first scene of the show Rick and Shane respond to a call of a police pursuit.  Rick's keychain can be scene and it is a plain white circle with some numbers on it.  Probably police issue since it is so plain.

Psych Season 4 Episode 8 "Let's Get Hairy"

A man goes to Psych thinking he is a werewolf and asks the guys to watch him during the night. They fall asleep and it seems the man escapes and jumps through their window leaving a tuft of  hair on the broken glass.  They take the hair to Juliette for her to test.  They keep it in a keychain coin purse.  Juliette says that she had one as a kid.