Consumables for facing a tougher party?

[zlefin]

In both 3.5 and pathfinder; what consumables would be good to have as an emergency measure if facing a party/force that's tougher than you (imagine an equal size party that's say, 3 levels higher)? Obviously you'd be at a severe disadvantage and a risk of death, so burning through consumables, even very expensive/risky ones, to have a chance at winning could be worthwhile.

Interested in all level ranges and optimization levels; this is more for planning/dm'ing/worldbuilding.

[Biffoniacus_Furiou]

Potion of Displacement- 50% chance for attacks to miss you.

Wand of Swift Invisibility- swift action to activate per the Rules Compendium, use it at the end of your turn, or before you attack if needed.

[Elkad]

Vigor tattoos, at as high a ML as you can afford/find. 100gp for each 5 temp hitpoints if you buy them.

Same witha bunch of other augmentable psionic buffs.
Force Screen, Inertial Armor, Strength of my Enemy, Precog-Offense, Precog-Defense, Prescience-Offense, Synesthete, Biofeedback, Expansion/Compression (2 sizes and 10min/level if you pump it up), multiple copies of Energy Adaption(specified), and I'm sure there are more.

[sleepyphoenixx]

CL boosters. There's a bunch of 1-shot CL boosters like Terran Brandy (BoVD) or Hero's Tears (CC).
Most of them are restricted to spells with certain descriptors (most often good), but there's ways to get that on any spell and most of them stack.
And getting a +4 or +6 to your CL will obviously be very helpful, if only for a dispel check against their spells.

There's also a bunch of optional material components in CC that no spellcaster should leave home without (if they have the right spells on their lists).
Of note are the Pearl of the Waves and Aural Sapphire which let you quicken any spell with the water or air descriptor for a few hundred gp a pop.