@HoloDreamer trust me they are not :). If u really want cheap keys, u can get them for 2-5$ depending on version - exactly the same keys.
But if u really doubt me just mail/call MS and give them your key - they will tell u

@All i hate to burst your bubble but all those keys are MSDN/Bizspark keys, and are illegal to sell - and will be revoked, can be anywhere from 1 to 6 months, but trust me it will happen.
I have had enough of those keys to know alot about them