I concur with euplusia, sure looks like a Maxillaria and could be an albescent form. Looks a little like callichroma in the lip details, probably not that species but maybe not too distantly related? As Carrie said, photos of vegetation and growth and blooming habits may aid in identification. For other ID resources, check out:
Orchids Interactive--a smaller forum that has several very knowledgeable species growers; the late Dr. Eric Christenson, a Maxillaria expert, used to post there sometimes (username 'botanist') and might have ID'd something similar in the past. Even if not, chances are good someone can point you in the right direction.
Eric Hunt's Flickr photostream--many excellent pictures of orchid species, including lots of obscure/rare ones
Swiss Orchid Foundation Herbarium--a great resource for ID'ing obscure species
Internet Orchid Species Photo Encyclopedia--last but not least, a really great and comprehensive resource though not always 100% accurate or up to date (not that the other sources mentioned necessarily are).
I hope this helps!
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