The "empty" command.
I was just now thinking, 'twould be a handy thing to be able to use the 'empty' command to empty waterskins or vials onto other objects. For example, ye could empty a dispel magic vial onto an illusion to pop it. Or ye could empty your waterskin onto a flaming object on the ground in order to douse it. There are any number of possibilities.
First off, very few (two, maybe three) spells that can be cast with potions affect objects. That means it's relatively sizeable chunk of code for little or no effect (but burning objects, you might scream, falls under the same thing... trust me, the later is getting greatly expanded in the future).
The second one is merely logistical. Potions, by their nature, are meant to interact with animate things, not inanimate. It has to do with their affects based on modifying body chemistry, even if that means magically altering it. If it were left entirely up to me (and I had all the memory and code based resources I could ever want, potions would never duplicate spell affects, they'd be a class of their own, totally different affects entirely, but we don't have that luxury currently, so we make do with what we have). Anyway, I currently don't see any reason to make potions affect objects, other than the fact it would be 'neat' or 'handy' and whereas I've coded similar things in the past, they generally have a place in the overall scope of the game, which I don't see this having until occassion arrives where it would be both wide spread in its use, fit the fiction, and made logical sense within the overall design of the game.
Others, of course, are entitled to their own opinion, and I'm willing to listen =)