Saw a bird eating spider about the size of my hand getting scull dragged up the inside wall of a nursery igloo (shade cloth covered building for plants just so no one gets confused!) by a wasp a couple of weeks ago, it was one big, nasty looking wasp. I took my phone out to get a photo but the wasp dropped the spider and started flying around me, I think it felt threatened by my presence. I didn't hang around to see if I'd get another photo opportunity.
It was in the whitsundays in Queensland, I've seen tons of bird eaters up there but never seen a wasp like this so if anybody knows what sort of wasp it was I'd like to know. Unfortunately the best description I can give is that it looked like a wasp, was yellow and half the size of the spider (the size of my hand including legs not just the body if you know what I mean) it was skull dragging which looked like it was still twitching.
Don't worry, I think I might have found it , check it out by googling "tarantula hawk wasp Australia" and look at the pictures. They look to have orange wings but I definately remember yellow on the one I saw. Apparently their sting is excruciatingly painful, but doesn't last long on humans...