In my Black 2 playthrough, my team had two Psychic types in Sigilyph and Starmie, plus two Dark types in Zoroark and Drapion. I nearly boxed Gigalith for Roserade, which would've given me two grass types paired with Serperior, but I went against that decision in the end. Would've given me three double-ups across the board, but meh.
Member of Kid Icarus: Uprising clan Angel Strikers. Official Zorua of the Pokemon X / Y boards.
In most of my in-game teams since D/P I've had two Steels on my team, namely Lucario and Magnezone (B/W being an exception). I don't use them for their Steel type, but hey, having that many added resistances and Poison immunity is always nice. In my new playthrough of Soul Silver, I have three Steels, as I chose Skarmory to be my flier.
On the note of Skarmory, I end up with two Flying-types if one of them is Dragonite, as I usually use Dragonite as a fighter with the other one being the flier.
When Snake sees a "!" over someone's head, he runs and hides. When the Pokemon Trainer sees a "!", he beats them up and takes their money.