MIL always says "them [nouns]", and "what" where she means "that" or "which". It makes me almost homicidal.
"Them books what you bought the other day."
Aaaaaaaaaaaaaaaaaaaaagh!!!!
And DW - who in most other ways is a precise user of language and a bit of a stickler - allows herself to lapse when in the presence of her ungrammatical Northern family. So, for example, when talking about her sister, she will say "Me and Jane are going..." I can never stop myself saying "Jane and I".
And they all just look at me as if I have broken wind.