face-dusting
Face-dusting is when you take a shot at your friend on Facebook or Twitter, and then you run like you just stole the last cookie from the cookie jar.
Your friend posted a picture of their breakfast. You comment, 'That looks like a breakfast for a hungry zombie.'
Your friend posted a tweet about their bad day. You reply, 'You're just a sad cup of coffee.'
Your friend posted a story about their vacation. You write, 'That looks like a vacation from hell.'