Actually, speaking of eggcorns reminds me of one of my favourite recently-discovered words: "mondegreen."
A mondegreen is similar to an eggcorn but refers to something that has been the subject of a number of threads on fmttm over the years, misheard song lyrics. Here's an extract from an online article about this.
"The name "mondegreen" was coined by a writer named Sylvia Wright who misheard a line from a 17th-century Scottish ballad.
Ye Highlands and ye Lowlands,
Oh, where hae ye been?
They hae slain the Earl of O’ Moray,
And laid him on the green.
Unfortunately (or perhaps fortunately for the future of word play), Wright heard the last line as “And Lady Mondegreen” instead of “And laid him on the green.”
One difference between an eggcorn and a mondegreen is that an eggcorn typically retains the meaning of the original phrase whereas a mondegreen usually alters it completely.