When you hear someone say your name.
When someone attractive walks in.
Asking someone for a favor and trying to look cute.
When you see someone you know unexpectedly in public.
When you see someone you don't want to talk to.
Here are a lot of Sherlock, Firefly and some other GIFs:
A little Star Trek
Pirates of the Caribbean
This GIF starts with Yes..Yes. This is a fertile land
After coming here for a while you may have one of many different reactions.
Or you may think:
but all I can say about doing these kind of posts is:
And your welcome anytime!