While I don't necessarily agree with the "it would be awesome" reasoning, I do see use for something like that. Thus, I second Essence's idea.
Take it a step further. Buffdurationscalebyname="" / Buffstackscalebyname="". Although scaling by drunkenness and fullness specifically could get very overpowered in short order I must say, since it's the only buffs that can have their durations increased by adding more of the same. You could open the door to a zoo, close it again, eat say 10 deep omeletttes, and have a 350 duration fullness buff.
Which is why some sort of cap for that would be optimal, too. Buffdurationscalebylimit="", or something like that.
scaleLogarithmically="1" base="X" (this would be awesome and not that bad of an idea; If it were say 4 then you'd get 0 at 0-1, 1 at 2-7, 2 at 8-31, 3 at 32-127, etc) Actually logarithmScale might be a nicer, more brief way to name it. And base is only there because of rounding.
an expScale could be awesome too for making highly discriminating spells that scale off of TARGET stats rather than player stats. Both logScale and expScale could default to e as the base if another isn't specified.
Oh god, logarithms, those were bad enough in math class. But anyways, I like this idea. Scaling with number of buff stacks could have some interesting applications.
Who said anything about you hitting for that sort of damage? It's obvious that this is the new formulae for Dredmor's melee damage of Going Rogue.