Fire effects should have a (high) chance to burn non-metal items on the floor and make booze/potions explode. Maybe in GR, this could also happen to your equipment or things in your inventory. That would be cool.
I would support this, even if it only effected explosives. This opens up so many possibilities, you could drop bombs on the floor, poor out some gas/ alcohol, then lead a mob (zoo is preferred) through them and..
Well, only if you made sure it was balanced, and not overpowered and silly. Also, this is not the Tower of Eternal Flames in ADOM. We don't really need that here. Unless you want to add in two Blessed Rings of Ice, Fire Immunity on artifacts, Crowning to make you fire immune, or corpses of fire dragons you can eat to gain Fire immunity. Maybe if it only affected things on the ground itself, and rarely, and it depended on what the item was.
I was thinking in a Dredmor playthrough.. that it would be really useful if doors could be broken down with ranged attacks/ AoE/ magic. This seems related to magic damage effecting items, so I might as well post it here. Anyway, this would allow mages and rogues to set up traps before opening a door without the risk of activating the traps him/ herself (if it is currently possible to open doors like this, then please clarify).