The little dimple
that can be found right under your nose
. A great
place to rest
the end of your point
(or a Faber #2 pencil
) when thinking "hmm
I'm not sure of the exact "reason" for the philtrum, so I guess it's right up there with the appendix although I've never heard of anyone having to have an emergency filtrumdectomy. Perhaps it provides a clearer path for for air flow during sniffing. I have some time booked at the local wind tunnel to test this theory wish me luck.
I once mistakenly believed that the word was spelled "filtrum" luckily geeklizzard enlightened me.