Coolest hat:
coolest homo: Elton John
coolest mode of transportation: FLYING CAR
coolest old person: Harrison Ford

If he's too young, then Sean Connery
coolest period in history: the Industrial Revolution in America and Europe
coolest madman/lunatic/nutjob: Dahmer
coolest animal: blue whale, otter (they use tools!), or humu humu triggerfish
coolest sound: the "coin" sound from SMB