A catchphrase born from the brilliant mind of Rowan Bettjeman of Viva La Dirt League to describe something as being great and is a catchphrase that definitely exists.
A Douglas Adams original, was used multiple times in his book "The Hitchhiker's Guide to the Galaxy". Usually (but not necessarily) following "a load of", dingo's kidneys means rubbish, bollucks, crap or bullshit.
Seriously? I have to give an example in a sentence? I can't just leave it blank? WTF?! That's a load of dingo's kidneys!