While I was visiting family a couple weeks ago, my sister, father and I decided to come up with a plan to ambush my uncle with water balloons once he got home from work. So, my sister and I spent the afternoon filling up these balloons and I didn't want to fill them up TOO much, because otherwise they'd all burst before we got a chance to throw them.
So, first of all, the sneak-attack failed miserably because he saw us hiding, and then we started throwing the water ballons. My first one hit his side and unfortunately it was at that moment that I realised that the balloons weren't going to pop at all because they hadn't been filled enough. What happened next was my sister, with her ridiculous aim, whapped my uncle right in the eye with a water balloon that bounced off and landed in the bushes.
He definitely had a black eye for the rest of the week.
If that's not an epic fail, I don't know what is...