I was looking at the Goliath race, and noticed the Powerful Build racial trait, which lets me wield a weapon one size category larger without penalty. I also saw the Wield Oversized Weapon feat, which lets me treat a weapon as one size category smaller and lighter than otherwise.
Powerful Build: […] A goliath can use weapons designed for a creature one size larger without penalty. However, his space and reach remain those of a creature of his actual size. The benefits of this racial trait stack with the effects of powers, abilities, and spells that change the subject’s size category.
Wield Oversized Weapon
You can treat any weapon as if it were one size category smaller than normal and one category "lighter" for the purpose of determining the amount of effort it takes to wield. […]
This feat subsumes the effects of the Monkey Grip feat. The feats' effects do not stack.
Since one affects the weapon, and one affects the character, I think they would stack. So I could use a Huge greatsword basically as a medium two-handed weapon. My DM lets us use epic feats the same as regular ones, so that's not an issue. So, my question is, using these two features, what is the largest possible weapon I can use (The character I was thinking of uses this as the only criteria for a weapon's quality)? Also, how would I go about satisfying the prereqs for Wield Oversized Weapon as quickly as possible?
EDIT: Also, would Gloves of Enlarge Weapon stack with this for a Gargantuan Greatsword?