Everpresent enchantment

[Dancingdeath]

I don't know if something like this already exists but I thought of an armor enchantment for high level items that I thought was neat.

Everpresent- This enchantment can only be placed on armor. The wearer retains his full AC versus all attacks. Touch attacks, sneak attacks, ethereal attacks, and any other type of attack. Note that this does not render the character immune to attacks that require you to be caught flat footed. If you would lose your Dexterity modifier to AC without this enchantment then you still qualify as a valid target for attacks that would normally require you to lose it. The attack is simply made against you at your full AC. Everpresent let's you retain all modifiers to AC regardless of the situation. These are Dexterity, Force, Sacred/Profane, Natural Armor, and Insight bonuses to AC. The singular exception to this is cover bonuses.

I have no idea how much something like that should cost. And I may have missed some types of AC modifier. If i have chime in with them and I'll edit them in later. Thanks for the input.

[Dancingdeath]

Using 3.5 rules. Should have specified.

[Crake]

I'm not aware of anything like this existing in 3.5. It's worth noting that if you're looking to homebrew, most AC bonuses are universal, so you don't need to mention things like deflection, profane, sacred etc etc. The only ones that matter are armor, dex (and by extension dodge, though if dex applies then dodge automatically applies, so you don't really need to mention it), shield and natural.

As for the cost and value of the armor, well, that varies a lot from caracter to character. Arguably uncanny dodge is valued at a feat, since you can get it with shape soulmeld (impulse boots), but the ability to boost your touch AC is much more valuable.