Well quite often when I'm about to start slipping on the internet I get a call from either my friend or my mum and I have to get up and answer it. It's happened too many times to be pure coincidence. Once a few years ago I was in the middle of watching porn when my friend called me and wanted to talk about falling - too much of a coincidence too looking back.
Other times, there are some really hot girls I want to check out in greater detail but when I turn my head to do so something has moved to block my view. Either the girl has moved behind a lamp post or somebody has walked in front of her obstructing my vision. It's like I'm God doesn't want me to see what I'm not meant to.