Welsh pronunciations (of English words)
I'm sure you can all think of some rather idiosyncratic pronunciations and spellings. Ones that come to mind immediately are:
Co-op (as in Co-operative)Cwop
Post OfficePost Office
I've even know someone to pronounce Cambrian as Cam-breye-an.
updated by @gaynor-madoc-leonard: 11/11/15 10:37:46PM