a ‘m00b!’ is something that afflicts many people across the world, it is simply a smelling mistake.
I really hate it when someone /kill s in a firefight, not only does it deprive you of the xp but what’s worse it denies you the satisfaction of the kill.
I dislike people being in my way when trying to run somewhere in a hurry, especially on the first spawn of the map, I always seem to be the first one moving, and when there are other people spawning with you, you invariably get stuck behind a soldier carrying a panzer and surrounded by others so you can’t move for another few seconds until they’ve realised they’ve spawned. I know that’s a bit harsh, but it does irritate me. I like to be in the enemies face before they realise it 
Field ops who don’t give out ammo.
Medic’s who insist on finishing their firefight before reviving you.
People who repair the truck before getting the gold, especially when you’ve had a good run and taken out the contents of the bank (not including the gold).
People who don’t shuffle when the teams are oh so obviously unbalanced.
People who complain for being TK-revived.
People who throw smoke grenades on their own team’s snipers because they think the Covert Ops class shouldn’t exist.
People who think the Covert Ops class shouldn’t exist.
Honestly, it does grate me a bit when people finish me off when I’m wounded and waiting for a medic, but that’s part of the game so I can’t really complain.
People who TK me when I’m on full health and after I’ve announced I’m a covert op with a uniform on very low health and I have a very large blue exclamtion mark above my head. Oh, and don’t forget the huge red circle.
People who set off enemies mines as I spot them and then I get taken out by the mine, usually along with them.
How to annoy players? Well, as a medic you could go up to someone wanting a revive and poke at them constantly with a glow stick without ever hitting them, so hopefully they’ll miss their next spawn. Try to poke other players with your glow sticks when they’re alive when they’re asking for medikits. Also, drop medikits on dead people.
Had a game the other night with two friends, just showing one of them who’s new around the maps. We were on railgun and I played an Allied engineer against the two of them. I kept planting mines around the track switch and other places I knew they’d be going. About 5 minutes from the end I found out that they couldn’t see or spot the mines with a covert op. They were a bit pissed at that.
Oh, and it does annoy me that some servers kick you if you alter your name or sometimes even your controls. I know it’s meant to stop people who try try to be funny by imitating someone but it is annoying none the less.
(i have done it only once cuz usualy i play fair and fun games)