I'm old enough to remember the days when computers worked in one font, and one font only. OK, it was a problem if you wanted to type characters in a foreign alphabet, but other than that everything worked.
These days we're exhorted, obliged even, to use a sans-serif font, which from my perspective is a pain. I've had a number of phone calls from people expecting to talk to Lain, simply because it's an unfamiliar name, and their font is set to something which can't distinguish between an upper case 'I' and a lower case 'l'.
PS: Curiously, there was an article in the Guardian (at http://www.guardian.co.uk/artanddesign/2010/jun/20/in-defence-comic-sans-font). One of its advantages, for me at least, is that it doesn't suffer from the same I/l problem as Arial.