Ways to get earth glide?

[Zetapup]

Like the title says, what ways are there to get earth glide or similar abilities? The only two ways I can think of (without being an earth elemental) are to go into the earth dreamer prestige class or to cast earth glide (RoS).

[Biffoniacus_Furiou]

Elemental Wild Shape or Shapechange.
Paladin 12 with the Underdark Knight ACF in Complete Champion.

[TrueJordan]

dndtools.eu/spells/spell-compendium--86/xorn-movement--4491/ or that spell Undermaster or something that's a highish level Druid spell that grants a bunch of Earth related SLAs