The other day I was playing with my friends in a party. 6 of us vs whoever else joined the game.
We were trying to see what all we could do if we communicated.
#1. We decided to have an all knife round. The 6 of us using knives against the other team with guns. We let ourselves use special 'nades though. We ended up winning (It was demolition!)
The coolest part was when they had armed the bomb at A, and we all just threw in all the special nades we had, knives "blazing(?)" and captured A within seconds. The entire team was guarding A and we killed them with knives. Then, promptly after that, we got 5 guys to stalk one of their players and lead him into a corner. That worked out perfectly.
#2. We wanted to see what would happen if we unleashed ALL our killstreaks at once. AC130+Attack Chopper+Stealth+3 Predator missiles+Chopper Gunner+Precision Airstrike... The enemy was in our complete control for the rest of the game.
#3. Early on in the game I had gotten an EMP from a care package. I decided to save it to see if the enemy would try to pull a #2 on us. Halfway through the game, one of my friends got his first nuke ever. He was so excited, nothing could've ruined his mood... Except for, say, an EMP just seconds before the nuke was about to detonate.
Yup, I'm a dick.