Hi - this is my first post but thought it was about time (seeing as I'm a Brit...)

Crikey - (polite) surprise
To be knackered (rhyming slang - cream crackered) to be very tired
To take the mickey - to mock someone. "Are you taking the mickey?"
Tickity-boo. This means fine, OK. "Everything is just tickety-boo".

Bye for now...Oswas