This 'public service announcement' exists:

Why on earth would it be Patty rather than Paddy, I hear you ask? Well, it's a simple case of homophony. Two identical-sounding words, one pronunciation, confusion abounds.

What's that? They're not homophonous? Not to you, maybe. Yer average British English speaker will pronounce these with a /t/ and a /d/ respectively, or possibly a glottal stop instead of the /t/. Yer average American, on the other hand, will have what's called a 'flap' or 'tap' instead of the /t/, and this sounds so much like a /d/ it's pretty much indistinguishable and they're pronounced exactly the same.

I'm ashamed to say I don't know how yer average Irish person would say them - my instinct is telling me there's variation between the flap and the /t/ and /d/ distinction, but I don't know. But then any Irish person is likely to know how to spell the name of their patron saint in any case, one would hope.

Fox gloves and puns

I've got a pair of gloves (those fingerless ones with mittens that flip off so that you can work your phone) that have a fox design, from Primark:

Fox gloves from Primark [photo source]

I've been wearing them for some time, and refer to them as my 'fox gloves'. I shift the primary stress to the first syllable (FOXgloves), indicating that I consider this to be a compound. During the time I've owned these gloves I've said the word 'foxglove', referring to the flower. And yet I've never, not once, realised that it would be hilariously witty to refer to them as foxgloves until this morning, when I wasn't even wearing them (it's proper winter glove weather now).

This is testament to the power of our language faculty to keep homophones apart. Puns wouldn't work, for instance, if we were constantly aware of similar-sounding strings. There's a joke which goes like this:

Two cats, one called OneTwoThree and one called UnDeuxTrois, were having a swimming race. Why did OneTwoThree win?

Because UnDeuxTrois cat sank! 

This joke works because UnDeuxTrois cat sank is exactly homophonous with un deux trois quatre cinq (the numbers from one to five in French) for many English speakers, not to mention this set of numbers being learnt pretty much as a 'chunk' or formulaic utterance by the 8-year-olds telling this joke, and so we are presented with a situation in which our brain is temporarily confused by the words, finds the humour and then has a good old chuckle.

Not all puns are exact homophones, and one of my favourite jokes is this one:

Why are there no aspirins in the jungle?

The parrots eat 'em all!

This pun relies on parrots eat 'em all sounding like paracetamol, but in fact I pronounce paracetamol  the other way, with an e as in bed (something like /ˌpæɹəˈsɛtəmɒl/ for the linguists), and my all is not like the ol syllable. Nevertheless, there are many puns that work because a string of sounds is precisely identical with two different meanings, and yet our brains don't ever confuse them until we are made to by the complicated joke set-up. Similarly, we don't ever seem to get homophonous words mixed up (pen, bank etc., where the words have two or more totally separate meanings). We even manage to think of different lexical categories from the same root as different (analyses is one I use in teaching: it can be the plural of the noun analysis or the 3rd person singular present tense form of the verb analyse). How we store and retrieve these is a question I'm going to let the brain scientists work on.