A D&D 3.5 campaign that I ran over MSN Messenger in the summer of 2010. The very first game started in a tavern when the party was randomly recruited by a city that was under attack by Drow forces, the captain of which was another player (who I'd make sure would switch to the party's side with shenanigans). I believe I ended the first session when the party + the Drow PC were trapped in the tunnels from which the drows came, and the second game was an adventure through an underground dungeon where the party released a BBEG and started working to stop them for the rest of the campaign.
When I look back on it, I basically committed all the cardinal sins of DMing: Starting in a tavern and later forcing down a needlessly strong plot hook, setting up PvP and betting that the party will come together later on... It's a wonder how that campaign survived as long as it did.
Then again, I remember the game not taking itself very seriously. The Drow PC was named Trizzt To'urden (and was of course a ranger with two scimitars), and we had a Halfling Rogue (later got the Assassin prestige class) named Dungen Siage. I had just finished Fullmetal Alchemist Brotherhood at the time, so I had also shoehorned in Alchemists that work with transmutation circles as a player option. It was very much a mixed bag, but it was a nice way to spend the summer. I can also proudly say that my very first campaign finished its entire story arc succesfully, which not a lot of people can do I reckon!