The old standby of: h*tp://www.youtube.com/watch?v=e1IxOS4VzKM. The letters and numbers after the = sign is what you want to paste between the youtube tags. The letters and numbers that follow the equal sign are the video code.
Like this: [youtube*]e1IxOS4VzKM[/youtube*]
The end result is a video right in the post but doesn't work here. How do we do it in the Forums here?