Well, this is for people who play rogues that want maximum profits at other people's expenses. Even for a few copper.
Stealing Mob Kills: Wait until someone is down halfway through the mob and gank them. Rogues are probably most notorious for this. Steal mob and profit.
Stealing Chests in Instances: If there is a locked chest and the people you are running the instance with people that don't know you, play the little "I can't open it yet" and leave the chest alone. Come back later after you are finished with the instance, open chest and profit. *note* Resist the unrealistic/realistic offers of opening a lock box. They lie!
Stealing nodes/quest objects: Found an opposing faction mining away at your rocks? Picking up your weed? Sap them and open it! See someone stealing your quest objects? Sap them and open it! See someone looting a chest? Sap them and take it! Works best if you have camouflage. Very good at spiting people. Steal stuff and profit!
Running a lowbie through instance: Whether it's for twinking or just because you decided to be nice at the moment, set it on free for all so you get everything or master loot to manually distribute it to yourself. Before bosses, purposely get the person you are running dead on a few trash so they will run back. Make an excuse saying the boss aggro'd and out of flash powder etc, kill boss. Loot and profit!
Stealing Mobs II: Need shadowstep. Look for someone about to engage the mob, shadowstep, attack, and they won't realize that the mob has already been tagged. Also works if you're already waiting behind the mob. Loot and profit!
Stealing loot in instances: (Works with all classes but rogues are infamous for this as well) Roll need on items you don't need. Receive loot and profit! Say it was an accident, apologize, whatever.
Stealing loot in instances II: Get leader somehow, such as saying you want to mark etc. Set on master loot before boss and say it's to prevent ninja'ing. After boss is dead, check out his loot. See what items it dropped and pick one or two for yourself. Link the other loot, have them roll, if no one gets suspicious you don't have to explain yourself. (Of course don't give in to your rogue instincts and get greedy) After group leaves give yourself the loot you want. I did this with the recipe for Flask of the Titans from UBRS a looong time ago. Also for a couple of Felstrikers, too. (Was running for the Flask recipe so I made sure to -not- lose the recipe) Sell/keep for yourself/ and profit!
Rolling on crap people think you need: Roll on any leather with agility or stamina! Or a combination of both! Of course, your current gear cannot directly overpower it... it might have some different stats like dodge rating so you can say you like dodge... and people won't ever be suspicious! Disenchant/Sell and profit!
Staging a duel: Outside of Orgrimmar/Alliance equivalent dueling place ask someone in a whisper to do whatever to them. Halfway through pretend you beat them and rub it in their face! Good to embarrass people such as those snobby epic gladiator warriors! *Note* Doing this to serious people will get you a forum post and a screen shot. Embarrass and profit!
Farming Spot Thief: Find someone from your own faction and mark all the mobs before he/she does. Although he/she will still get some mobs, but you will get more AND spite people! Make people angry and profit!
Stealing Boss Loot Without Suspicion: One of the rare scenarios where everyone is dead and the boss is dead but you were smart enough and rolled a rogue, so you vanished. Ask for leader somehow and get it! Make a macro and spam party chat, secretly change looting to master, distribute yourself the loot, disconnect, and voila! You have the loot! If they ask you afterwards play the "it's Blizzard's fault" game and profit without suspicion! Steal and profit!
Pickpocketing: Follow someone around that's farming/killing humanoids with pockets to pick. It might be safer if you sap if the person's on the opposing faction and/or outgears you considerably. Pickpocket and profit!
PIckpocketing in Instances: Before you sap a target pick every single mob! Although your group might get frustrated from the delay. Pickpocketing is a skill to master! (I mean it) Pickpocket and profit!
More to come! My 3rd year anniversary of being a rogue is almost coming so I thought I should make partially satirical/serious topic on profiting from occasions you never though you could at other people's expenses!