I often come across web pages that use fonts that I like and wonder what they are (I'm not that good at guessing fonts). On the whole this situation happens while reading on my iPhone because that's the only high-resolution screen I use - good fonts look amazing on the iPhone 4S.
This just happened to me while reading a post linked from daring fireball - the “of course” principle of design. I really liked the look of that font on the iPhone. (I also noted that I should reduce the margins on my blog for small screens because you have to zoom to read really). So how, on an iPhone, you do find out what font that is?
For your copy/paste convenience, I have provided the code for the WhatFont bookmarklet:
Turned out that that post was using Crimson Text from Google Webfonts. Nice.
It looks like Crimson Text is a promising free font that might have Polytonic Greek characters at some point so that's useful to know for me.