Crazily, ridiculously and utterly obsessed.
This word is often used when refering to crushes, but can be used to say someone has found a new favorite pasttime. Can sometimes mean dangerously obsessed to an unstable degree where one's friends seriously worry about that person's sanity.
The word "flinthired" originated when a very wise person said, "she is so obsessed with him, she would let him hire her to strike flint on a rock all day long."
This word is also an excellent scrabble play.
Amanda: Omg, Did you hear about the newest guy Carolyn is flinthired with?
Abby: yea, she's got it soo bad. She checks his away message every ten seconds...
Kellee: She NEVER stops talking about him...
Amanda: I'm really worried about her...I heard she camped outside his house last night and hasn't eaten anything but olives since he mentioned he liked them a while ago.