Bigger then normal dmg dice 2-handed weapon?

[Zweisteine]

Referencing the Ginormous List, there are three weapons that deal 2d8 damage.

The Sugliin, from Frostburn is a two-handed primitive exotic weapon that apparently takes a full round to attack with. It is basically a large stick with antlers tied to the half you aren't holding.

The Great Crossbow, from Races of Stone is exactly what it sounds like. A bigger crossbow. It also happens to have the critical range of a rapier (18-20), but does not benefit from Rapid Reload by RAW, so isn't so great at high levels without finding a way to make it reload itself.

The Fullblade, from Sword and Fist (a 3e supplement), is a bigger greatsword (actually deals damage as a large-sized bastard sword) that requires exotic proficiency to use, because it's so darn big.

EDIT: The last one got ninja'd in while I was making sure I had everything right. Not much useful info here, then.