An article or blog, read on the computer, that is so fast moving, interesting or captivating that the reader is anticipating the what the next screen, by scrolling down, will hold. Similar to a 'page-turner' that a good novel is referred to.
"Justin's new blog on his movie review website was phenomenal, a real screen-scroller. I couldn't take my eyes off of the monitor."
"Did you see the latest rant on Justin's blog? It was a real screen-scroller because I couldn't wait to read what he was going to attack next."