Didn't there used to be a spell, probably from 3e, that allowed you to deliver touch attacks with it? Spectral hand, maybe?
My only arcane caster in our 3e campaign is a Sorceror- and she doesn't know any touch attack spells. (thus, it has never come up) And a good thing, too- she can't hit the broadside of a barn- from inside of it. She has yet to hit anyone with acid splash or ray of frost- even though she casts them regularly...
Mage hand always struck me as a spell that could have been useful- if it had been allowed to be. I suspect it probably IS useful in some groups- that ignore the 10# stipulation. (a great example of D&D giveth, and D&D taketh away, lol) For example- it's the perfect thing for a mage that can't be bothered to get up and grab that book off the shelf, or that beaker o' stuff from the other side of the lab, or, or, lol.