For what??
My favorites are:
Venus Orchid---just because it looks pretty
Fragrant Fern--because if you add a lot of fertilizers to it, it really blooms nicely. Try it. Lots of huge flowers spread out all over the place. (make sure to let it fully grow to age 30 or something)
Yeah , that's right. Oh have you seen the post "Frangant Fern Frenzy"? in Plant Tycoon Garden Exposition? It show lot of pictures of Frangant Fern.