Yeah, but the problem with that is that with PDF the page layout is really set in stone. What's appropriate for a 24" monitor may not be appropriate to read on your phone, or netbook, or what not.
The best format, IMO, is plain HTML. It can come with a custom style sheet, or can be overridden to taste on the client. It can be read by anything, it can be endlessly adapted .. it's just the best overall solution, IMO.