I love malapropisms: similar-sounding but incorrect words, which sometimes have a humorous effect.
Here are a couple of recent ones:
Have you seen any funny word stuff? If so, do share!
Then, course, there's that famous Spoonerism, when James Naughtie on the Today programme introduced 'Jeremy Hunt, the Culture Secretary' - except he got the 'C' and the 'H' the wrong way around...
Someone else did it, too, a little later. Seems it was perhaps more of a Freudian slip. Or, as a colleague of mine at work years ago used to say 'A fraudulent slip.'