This was featured in the RPGTips newsletter and it has changed the way I read online. I find myself wishing I could spreed non webpage stuff: Spreed Chrome Extension
Basically, it shows you only one word at a time but flashes through the text at whatever speed you set. The default is 400wpm but I often find myself upping it to 500. My eyes don't get fatigued, my attention wanders less (so no rereading of passages), and, oddly enough, my comprehension and retention seem better. It's pretty good at picking out the main content of a page by default (so no worries about it reading off menus or footers). So far, I've only tried it on a couple of basic subs here, but it worked very well for that purpose.