User blog comment:XXEpicMage99Xx/Skyrim DLC Weapon Ideas by xXEpicMage99Xx/@comment-1992639-20120420212413

Combining spell effects. Fire + Ice = Water. Lightning + Ice/Water = Area Effect Lightning. And when you combine those spells enough you learn a new spell and can use that new spell directly without combining, thus freeing up a hand to combine that new spell with yet another spell. etc.

As for physical weapons, probably ones that you can use from horseback. And obviously then horseback battles (being blocked while doing a power attack from a horse could throw you off the horse).