In the spirit of empirical enquiry into the Nature of Things, especially Useless Things, my 10th level necro, Marcus, himself a sometime Useless Thing, did find a non-socketed Wirt's Leg and imbue same, to wit:
Despite the Wraith Blow Wirt's Leg's obvious and endearing qualities, I felt the enquiry would be incomplete without further study, and therefore engaged my 24th level barbarian, Bernard, to do likewise:
While the Havoc Grinder Wirt's Leg offers some few enhancements over the Wraith Blow Wirt's Leg, still I did not believe it to be state of the art where Wirt's Legs are concerned, and so my 33rd level paladin, Bard, was induced to sally forth as well. He returned with:
Marcus is now threatening to spend his 6 unused skill points on Dim Vision. Bernard had to be talked out of brandishing his Wirt's Leg on a bare-arsed run through Travincal, and Bard is studying assembly in the hope that he can find a way to return to Tristram as a Diablo 1 Warrior and beat the crap out of Wirt.
In light of these recent developments, I feel it best to leave further experiments in the field of Imbuing Wirt's Leg to others.