[Lonely Tylenol]

Updated with the following spells:

Spoiler

Spell Compendium
Create Magic Tattoo - 10th - 1,000 xp (on self) (12-24-2011)

Complete Mage
Attentive Alarm - Complete Mage - 10th - 1,000 xp (on object) (12-24-2011)
Caustic Mire - Complete Mage - 12th - 2,000 xp (on object) (12-24-2011)
Caustic Smoke - Complete Mage - 11th - 1,500 xp (on object) (12-24-2011)
Climbing Tree - Complete Mage - 9th - 500 xp (on object) (12-24-2011)
Ghost Lantern - Complete Mage - 12th - 2,000 xp (on object) (12-24-2011)
Nightmare Terrain - Complete Mage - 12th - 2,000 xp (on object) (12-24-2011)
Resinous Tar - Complete Mage - 9th - 500 xp (on object) (12-24-2011)

Sandstorm
Haboob - Sandstorm - 11th - 1,500 XP (on object) (12-24-2011)
Wall of Magma - Sandstorm - 13th - 2,500 XP (on object) (12-24-2011)
Wall of Water - Sandstorm - 12th - 2,000 XP (on object) (12-24-2011)

Eberron Campaign Setting
Detect Aberration - 9th - 500 xp (on self) (12-24-2011)
Zone of Natural Purity - 10th - 1,000 xp (on area) (12-24-2011)

Magic of Eberron
Adamantine Weapon - 11th - 1,500 xp (on object) (12-24-2011)
Hidden Ward - 9th - 500 xp (on object) (12-24-2011)
Detect Dragonmark - 9th - 500 xp (on self) (12-24-2011)
Clothier's Closet - 10th - 1,000 xp (on object) (12-24-2011)
Expose the Dead - 10th - 1,000 xp (on self) (12-24-2011)

Races of Eberron
Misrepresent Alignment - 10th - 1,000 xp (on self, others, or object) (12-24-2011)
Unseen Crafter - 10th - 1,000 xp (on other) (12-24-2011)

Forgotten Realms Campaign Setting
Moon Path - 13th - 2,500 xp (on object) (12-24-2011)

Player's Guide to Faerun (from the "comprehensive spell lists"):

Player's Guide to Faerun
Blindsight - 10th - 1,000 xp (on self) (12-24-2011)

Magic of Faerun
Speechlink - 12th - 2,000 xp (on other) (12-24-2011)
Suppress Glyph - 15th - 3,000 xp (on self) (12-24-2011)
Safe Clearing - 11th - 1,500 xp (on area) (12-24-2011)
One with the Land - 10th - 1,000 xp (on other) (12-24-2011)
Disguise Undead - 10th - 1,000 xp (on other) (12-24-2011)

Underdark
Reflective Disguise - 10th - 1,000 xp (on self) (12-24-2011)

Serpent Kingdoms
Fang Trap - 12th - 2,000 xp (on area) (12-24-2011)

Shining South
Arcane Sensitivity - 9th - 500 xp (on self) (12-24-2011)
Darsson's Chilling Chamber - 10th - 1,000 xp (on area) (12-24-2011)
Darsson's Cooling Breeze - 9th - 500 xp (on area) (12-24-2011)
Darsson's Fiery Furnace - 10th - 1,000 xp (on area) (12-24-2011)
Sea Legs - 9th - 500 xp (on other) (12-24-2011)

Unapproachable East
Greenfire - 11th - 1,500 xp (on area) (12-24-2011)

Originally Posted by Dracomortis

It's probably best to (dis)allow them on a case-by-case basis. Align weapon, keen edge, (greater) magic weapon, and weapon of impact seem fine, since they can't stack with similar effects. Weapon of energy might be too much since it explicitly *can* stack with the emulated weapon property and could arguably stack with different damage types of itself (i.e. have the acid, cold, electricity, and fire version of weapon of energy on the same weapon at the same time). Sonic weapon is anyone's guess: while all of the other spells explicitly state whether they do or do not stack with the emulated weapon ability, sonic weapon doesn't. I'd probably leave it out just for being ambiguous.

I think that's what I'll end up doing. I just wanted to make sure that it would be no great sin to do so on a case-by-case basis, or whether it should be disallowed by precedent.

Originally Posted by Viktyr Korimir

I'd say that any 24 hour duration buff spell without an expensive M component should be included-- you're essentially trading XP to free up a spell slot. Endure elements and mind blank come to mind.

On a case-by-case basis. I am thinking of doing this for Endure Elements and Undetectable Alignment. I want to say Mind Blank would be too powerful, but we're talking about a 16th-level/4,000 xp requirement... Then again, it does free up an 8th-level spell.

I don't know. I would have to think about that. In all likelihood, it will happen on a case-by-case basis.

Input on this matter would be appreciated, though.

Totally house rules territory, but have you considered removing permanency from the spell list as simply allowing anyone who can cast an appropriate spell to make it permanent by spending XP? One of my pet peeves.

Nope. The two rounds casting time of Permanency means everything in this regard, especially when you're talking about spells like the Walls and the Clouds, that have practical battleground implications that happen in real-time.