Some people on the official forums posted a very intriguing strategy called tri-lane.
It's basically 1-3-1 lane setup with no jungler instead of 1-1-2 (techically, the metagame in the US is 1-1-1 + roaming support). The three in mid are champs which don't need levels or items to succeed. For the most part, support champs.
To be specific, the characters they used were: Urgot top; Janna, Morgana, Sona mid; Tryndamere bot.
The objective for them was not to get kills. In fact, they'd often be down in kills. But they'd always be up in towers. So for that team and strategy, the game is not about last hits and pacing, but endless pushing. Since mid had an aoe healer and two great farmers / harassers, they would destroy mid tower before the other lanes could keep up. After that, all three in mid would move to another lane and push it 4-man and repeat as required to rush as many towers as possible.
They also pointed out that since their strategy is so bizzare, the enemy team is more or less never designed to take on three in mid. Since they'd have to switch their lanes around to try and counteract that strategy, they would be working less optimal than the team which actively sought out 3 in mid in the first place. For example, they'd have to sacrifice champions who might suffer a lot more from the lack of exp / gold compared to Morgana, Janna, and Sona. It was also noted that oftentimes the enemy teams would spend so much time moving between lanes trying to counteract the roaming 3-man team that they would actually be very close in terms of levels.
Honestly speaking, I think it's a very interesting idea. I'm sure a lot of people have tried 3 in mid before but I don't think anyone has thought of it as in depth as they have. I am going to take their analysis with a grain of salt, but I would very much like to try it out a few times. It would at least be a nice change from the super slow paced regular LoL.