What's the biggest Orchid you've ever seen?

[Kratos]

Went to a local garden center a few weeks back and they had lots of orchids past their primes and being sold off at marked down prices (resisted huge temptation), but came across one that was HUGE, searching the web still haven't found anything like it! Wish I had taken a picture... it had four tall flowing stalks, the pot was gigantic with a great many leaves.

It got me wondering, is it possible for normal Orchids to get to that size over many years or was it some type of gigantic Phalaenopsis species? What's the largest orchid you've ever seen?