The list of browsers you can test on includes MSIE 5.0 and 5.5. Do people target these browsers anymore? How old does a browser have to be before you say: I'm s

The list of browsers you can test on includes MSIE 5.0 and 5.5. Do people target these browsers anymore? How old does a browser have to be before you say: I'm satisfied if the layout is a little off, as long as it's legible?