Crack The Sads
My current favourite Oz expression is "to crack the sads," as in, I told her we couldn't go swimming today, so she cracked the sads. At least, I think it's Oz. A cursory googling seems to confirm this assumption, and it also doesn't seem to have been around for very long. I think it needs encouragement. I'm all for nourishing what little home-grown slang we still have left.
Last year I took up "Crikey!" so perhaps 2009 will be the year of cracking the sads. What with the dismal economic and climatic outlook, I should have plenty of opportunity to use it.