Lehrer's song "The Irish Ballad" is popular in filk circles and at renaissance faires nationwide. I wasn't able to find a clip showing him singing it (though there are some clips on YouTube showing him perform), and most of the non-Lehrer performances, even by people who have made names for themselves aren't as good as the original. However, I found an individual who lip-syncs a number of songs including a few Lehrer pieces, and he had the good taste to leave in the very humorous introduction. So here I present Ben (RonfarZ3) lip-syncinging Tom Lehrer's "The Irish Ballad" (with intro).
And now that you're all the way down here, I'll suggest that you watch (or at least listen to) the video before clicking any of the other links. My timing is nothing if not late. And as a bonus for reading this far, here is a YouTube Channel dedicated to Tom Lehrer.