Small white, purple and yellow orchid
 

I was particularly enchanted by this orchid at the Atlanta Botanical Gardens' Fuqua Conservatory, and I'm hoping to find out what species it is. Any ideas?

Thanks :)

Hi, welcome to the orchid board!

It looks like some sort of peloric Phalaenopsis.

Peloric just means that the flower form is more "regular" than is usual for an orchid, which are more typically irregular (lip of the flower does not look like the petals in most orchids, in peloric flowers, the lip and the petals are similar).

That flower looks like it could have the species Phalaenopsis equestris in it's background. Googling 'peloric Phalaenopsis equestris' shows a lot of results that are somewhat similar to this plant.