Couple years ago we were in Yellowstone, out by Slough Creek. Had a herd walk by. As one of the cows walked by I rolled down the window of the 4-Runner and said "Hi". She turned her head and looked at me as if to say "Are you really that stupid to try and get my attention when I am THIS CLOSE to you?".

Damn, they're big.

Thanks for all the ideas. The best, is of course, practice.