The act of learning information about a person because of thing posted on a third web-page or face-book wall. This is usually followed by the mentioned information being referenced later, and the person not realizing that what they said was viewable by non-friends. Thus leading to the incorrect assumption that that they were being stalked.
Jill Posts-I need a vacation.- Viewable to Steve's News-feed.
Jane comments. You should totally come with my on mine. I'm going to Costa Rica!-Also viewable by Steve
In an unrelated post later Steve asks about Costa Rica Trip
Jill-That trip was a secret! How did you know!
Jane- How did you know about my trip?! STALKER!
Steve-WTF? It was on my Feed! It was Accidentally Stalking at worst!