Someone asked back on the other thread about how to gain healing via elemental damage... here's a crazy one:
Monsters of Faerun - Giant Strider
large magical beast, 2 HD, LA+2 (LA from web update)
Str +8, Dex +2, Con +6, Int -10 (owch), Wis -2, Cha -2
Healing from fire (ex): Once during each 3 rounds that a strider is exposed to intense heat or flame, the creature gains the benefit of a cure light wounds spell (1d8 + 1 hp healed). A fireball spell or other intense, fiery attack fully heals the creature instantly.
All things considered, I think it's also the lowest HD/LA magical beast I've seen...
edit: oh wait I take that back, the Abrian (Fiend Folio) is 2HD/1LA