<Makes Show of Checking Tolerance>
Sadly not close enough...
Still not close enough... But you can have it. Both passenger and freight 747-8 variants have a MTOW of 442 tons. Properly heavy!
Your turn.
Bit of a guess, but I *seem* to recall they are thrown at monkeys (or maybe birds) in trees to knock them off?
And maybe Ethiopia?
<hides>
C
Wouldn't a monkey catch the boomerang and chuck it back?
I'd go for birds such as those that glide and in Australia (Cue QI klaxon)