Odd Rolls, Checks, and Saves

[Winterking]

I was reminiscing over past gaming sessions recently, and remembered a few strange combinations of ability checks, saves, and similar die rolls. Things like Reflex Saves using Int instead of Dex, or Profession/Knowledge/Craft checks for odd purposes.
Does anyone else have any stories of unusual rolls their GM had them make, or they had their players make?

Here's mine:

-Rolling Willpower to Soak Damage:
The campaign was an old World of Darkness amalgam, at semi-absurd power levels for most of the characters. Usually in WoD, damage can be soaked--prevented--by rolling some combination of Fortitude, and Armor, plus a couple of supernatural abilities. In this case, though, the evil Demonic antagonists (as in, Demon: The Fallen) were attempting to destroy the world via a ritual which created and then spread waves of extreme anguish, misery, and torment. Instead of the normal stats, this damage could only be soaked by rolling Willpower, which made sure that it wasn't just the hideous combat Vampires that survived.

-Profession: Sailor to avoid being Stunned
In my recent campaign, the PCs, generally piratical types, had just found the base of the legendary Pirate King, and were sailing into his secret cove, when they spotted the Perfect ship (if ships had classes, this would be a Paragon). And so I called for a Profession: Sailor check--anyone with a low result obviously didn't know much about ships and sailing, and so wouldn't notice the perfection of this ship, but high results meant that the PC knew a good ship when he/she saw one, and spent a couple of rounds in awestruck reverence.

-Int + Base Attack Bonus:
I had my players roll this a few times when they were getting the hang of new battle equipment, trying to estimate an enemy's threat, or other analytical combat-related situations. I figure that this combo reflects the ability to analyze a given widget, and the fighting experience that might suggest the manner in which an unusual widget would be used. This principle works elsewhere, combining an ability with some other score to get a rough approximation of knowledge/skill that is neither random nor denoted in rulebooks.

[Chronos]

I'm a big fan of using alternate abilities with skill checks, in the appropriate situations. For instance, to blend in with a crowd, make a Hide check, but using Charisma instead of Dexterity. And of course, many Profession checks should be modified this way, too, depending on what you're trying to do: A profession like teacher should probably be more Cha-based than Wis-based, while a longshoreman would rely mostly upon his Str.

[Roderick_BR]

It's interesting. I can see the first two working. The first is basically a will save to cut the effects of a mental effect magic that normally deals damage, and the other a skill check to prevent "terrain" effects.
Not sure about the Int + BAB, but I think it works.

[Golthur]

I often mix it up, tying whatever ability I think is important for the situation (I guess I've taken too many cues from White Wolf).

A typical example - one time to get information from a grizzled old sailor at a dockside bar, the PCs had to prove to him that they weren't "landlubbers". So, one Int + Rope Use check later, the party rogue talks his ears off about various sorts of knots. Done and done.