I drove through the McDonalds here a few years ago when it was new. The speaker you order from was terrible, you couldn't understand what they were saying. So the next day, I got a pair of walkie talkies, and held one out the window to the speaker, and ordered over them.

What, can you repeat that sir?
I did
I still didn't get that sir
I repeated it
Sir just pull around to window #1, I'll take your order there, thank you.
So I drove up to the window, laughing, and unprepared. I held the talkie up to the window, and when he turned around I ordered over it again, this time in person.
He was so mad, he grabbed the thing from my hand, and pushed the button, and said 3.68, please pull forward, and hande it back, and slammed the window.
I know it's terrible, but I still get a good chuckle out of this, and it's been quite a while ago.
Have you ever done something like this? Lets hear about it.