How about anything in american spelling? :thefinger
I can't stand the way microsoft programs just set the default to English US, and even when I set it to English UK, it still finds a way to change back whenever it feels like it. WTF?
Seriously though, what's with the random omission of letters from words and the insistence on using Zs everywhere, even when it is etymologically incorrect? Analyze?? Excuse me, what? This would be a word which has its roots in analysis? Analyse is the correct spelling.
As a Chemist, I dislike the 'alternative' spellings of elements in the periodic table. Aluminum instead of Aluminium. Sulfur instead of Sulphur. Many metals end in -ium. There's a reason for that, and the americans come along and say, nah, that's too hard to pronounce so we'll change it

Maybe if they pronounced their "u"s correctly they'd be able to pronounce aluminium.
I think I understand where American English came from, or at least I have a theory. I've always assumed it was because of the number of immigrants into the US in the early days, so you needed to simplify the english language to make it more phonetic (why isn't that spelled "fonetic", by the way?). I get that, I do, but it does give the rest of the world the impression that you're too thick to spell words without spelling them phonetically
Incidentally, this is a decent site
http://www.wsu.edu/~brians/errors/