The worst I ever saw was an advertisement on a bar telling prospective patrons about the availability of "snacks´s". This is so wrong I can't even figure out how many distinct errors were made. (And yes, that's an acute accent, not an apostrophe.)
In English I’m actually ok with it for single letters or abbreviations- “your writing uses a lot of x’s and y’s”, “Can you pack away the CD’s and DVD’s”, but this is a personal quirk and definitely non-standard usage.
The worst I ever saw was an advertisement on a bar telling prospective patrons about the availability of "snacks´s". This is so wrong I can't even figure out how many distinct errors were made. (And yes, that's an acute accent, not an apostrophe.)