Strange starfruit-shaped brown seed.
Pic: Strange starfruit-like seed.
What's this seed? It's a nice one, strange, oblong, five-cornered, starshaped once you've cut it up, and no, it's not any of the spices I know. Oh, and the background is light green, though the flash lit it up a bit too much.
The black dried thing inside the seed smells strongly of vanilla.
The thing looks like a mummified starfruit (Carambola), except that it's not all wrinkly and things, and it's hollow, with a single wrinkled black thing inside.
It's most like a beech nut, but those only have three corners, are lighter brown, and don't have dried-up black things inside but yummy light brown nutlike things instead.
Anybody? Many thanks.
Update 10Mar2009: It's Quisqualis indica, the TCM remedy shi jun zi.