One of the things on my to-do list prior to WoW's Cataclysm expansion is to hit up the old-world zones that are going to be changing and take one last look around.

Questing in Barrens, pre-Cataclysm. Starts at Camp Taurajo in the south, fly north to the Crossroads, then west to start the Counterattack! event. After a while, Krom'zar will appear so that he can be defeated and his banner taken.

This quest had been in my books for quite a while and it as very much non-obvious where to start it. Turns out that if you miss the event when it first spawns, you have to talk to the quest-giver NPC again and ask "Where is Krom'zar?".