We had a really fun game just now, 4 man premade with 1 random.
Basically we got owned pretty hard for the early to mid game. But then the enemy kept insisting on forcing baron fights. The first time I was telling my friends... "dude, they're doing baron right now. Seriously." And everyone was like "no way, they can't be". Turns out they were, but we killed two of them for it though they took baron.
8 minutes later they tried it again, but this time we were waiting there... kinda of... Well, our random banzai charged in and got instagibbed. But we managed to kill them all anyway because they took so much damage from Baron (and wasted all their cooldowns on our suicidal random). Baron didn't actually die though, so...
1 minute later... there they went again. Straight for Baron. This time it was only Nilocy (Cho Gath) and me (Morgana) who were close enough to stop them in time. So we became manly men and charged in. So, imagine this alright.
Giant, massive, screen-sized Cho Gath with a HUGE, MASSIVE 1000hp spellshield comes roaring out of the bushes charging straight at your entire team. They all ran like headless chickens. I'm not even exaggerating. They didn't do anything. They ran all over the place, panicking so hard. Essentially their entire team got feared for 5 seconds. Completely owned them and won the game.
Remember guys, don't force baron fights if you don't need it to win. Never know when a gigantic spell immune Cho Gath will show up.