Temporarily gaining templates?

[EndocrineBandit]

Is there any way to do this? Like through shapechange or something of the sort? Still be yourself, just a little different for a while?

[Khedrac]

The Ring of the White Wyrm from Frostburn grants the Half-Dragon (White) template for 1 hour per day (has some other abilities too).
The item's description suggests that there should be variants for other dragon colors.

What do you know - the ring in on the WotC web extract from Frostburn: link (http://archive.wizards.com/default.asp?x=dnd/fw/20030323a)

[Inevitability]

Lycanthropy can be gained and lost rather easily. In fact, a number of cheesy tricks are based on this.

[Necroticplague]

Not through standard shapechanging magics, because those are typically very explicit about not allowing you to add templates. This is for a very good reasons, as the limits on those types of magics are based off of HD, which templates don't change. So if you could add templates via Shapechange, there would be no limit as to how many you could add (with very few exceptions), and it would get hilariosuly stupid and overpowered really fast.

Now, that aside, I'm pretty sure there are some Cleric spells that give you templates temporarily, but the sames escape me. I could have sworn there was one that made you a half-fiend if you were evil, and half-celestial if you were good.

[Crake]

Not through standard shapechanging magics, because those are typically very explicit about not allowing you to add templates. This is for a very good reasons, as the limits on those types of magics are based off of HD, which templates don't change. So if you could add templates via Shapechange, there would be no limit as to how many you could add (with very few exceptions), and it would get hilariosuly stupid and overpowered really fast.

Now, that aside, I'm pretty sure there are some Cleric spells that give you templates temporarily, but the sames escape me. I could have sworn there was one that made you a half-fiend if you were evil, and half-celestial if you were good.

Yeah, there are the ones that grant you fiendish/celestial and half fiend/half celestial. There's also the collar of umbral metamorphosis which gives you the dark template, that's from tome of magic.

[Segev]

There are cleric and paladin spells in the Spell Compendium, as well as psionic powers in Complete Psionic, which grant the caster the Half-Celestial and Half-Fiend templates for the duration of the spell/power.

[The Viscount]

Binding Zceryll applies the pseudonatural template while you bind her.

10 Levels of Fiend-blooded gives you half-fiend till it disqualifies you.

Were you looking for something specific?