Keyboard layouts and symbols
It pains me to say it (as a non-American), but every other keyboard layout (yes, even or perhaps especially British) sucks to some degree, especially that poor runt of a left-shift key (when instead they could have inserted the extra key alongside right-shift, and given us two usably sized, albeit slightly smaller, shift keys instead of one useless one, and one that you barely ever use because the mouse is (more commonly) in your right hand).
The arrangement of symbols on a US keyboard is logical and sensible (single and double quotes on the same key, backslash and pipe on the same key and close to forward slash, etc), unlike the UK keyboard, where, just to fit in the £ sign, somebody seems to have sneezed over most of the rest and has moved most of the symbols to entirely random places.
If you then set a "compose" key, you're in business for just about every accented letter or typological symbol (yes: °C, ², ³, µ, etc, etc) that you might commonly need.
Perhaps it might make sense to add a "column" or two of extra keys to allow every Latin/Greek/Cryillic language to fit easily and have a more internationally-friendly keyboard (with due apologies to Asian languages), but, failing that, I'll go for a US keyboard whenever I have the choice (which, oddly, usually tends to be only Apple: it's virtually impossible to specify your preferred keyboard when buying a Windoze laptop in the UK, sadly).