Usually worn by these people: secret agent(s) and the current Doctor Who the 11th Doctor.
As well as Bill Nye and some classy scientists and professor(s) who can actually teach and not just ramble on. That's all.
If you wear bow ties, you are therefore; indubitably cool.
"Bow ties are cool!" -The 11th Doctor Matt Smith
"James Bond wears a bow tie. That is why he's awesome. Not because he's a fictional character super-spy created by Ian Fleming in 1953 with the novel Casino Royale currently being played by Daniel Craig." -a lesser known definition
Thank you BBC UK and America. You're forever pretty awesome.
-An American Fan