A blonde walked into a bar. She sat down and started chanting, " 37 days! 37 days!" The bartender asked what she was doing, but she didn't answer, just kept chanting "37 days! 37 days!"
Soon more blondes came in, all chanting "37 days! 37 days!" The bartender again asked what they were doing, and one of them held up a little kid's bunny-rabbit jigsaw puzzle and said, " The box says 2-4 years, but we put it together in 37 days!"