For me, the funnest part of this game is tilting the life out of my opposing laner and if I can manage to tilt the whole team then even better. I won't type in all chat but i will do subtle shit like spamming my mastery emote (which i have keybinded to the scroller button on my mouse) and laugh for a good minute on dead bodies even if it costs me my life, and making 1v1s really close (when they really aren't) and make sure I survive with less than 100 health just to really fuck with you. And after spending 30 mins of that, I assume the enemy is pretty riled. Mind you, at this point I still probably havnt touched all chat. Now, if I see the team responding to my actions then I know I got them and that's where I really turn up the bm, up until the end of the game where if we win i will make it my duty to say "gg ez" because if at this point i havent made you afk you at the very least must be extremely tilted. Before I say gg ez i just imagine this person whose been mad as shit probably slamming into his keyboard and shit... So after i type gg ez i figure this person has gone complete ape shit and probably (hopefully) damaged his setup, the thought of which brings me absolute joy.
NOTE: I only do this when I can tell my opponents are probably less skilled then i am and I only do this in aram and normals.
TLDR:
If you're the type of person who gets really mad when someone says gg ez, then I thank you. You're the reason I can still enjoy this game. : ^ )