KDE let's me setup myy font sizes, I always use huge fonts and I hate with a passion when devs pixel allign things and break the GUI when I use larger fonts.

I also get exasperated when I get asked to pixel perfect align checkboxes and the labels in web pages, each browser has different checkbox dimensions and styles, and aligning them how the designer wants means a lot of extra styling that will break on users that don't use the defaults(but the designerr wants his pixel aligned stuff on his Mac screen... also rewording messages to align in message boxes or labels