Source: Half-Life Fallout

20.000 Steam accounts have been disabled by Valve. The reason, piracy, credit card fraud, account hacking and more. Go Valve :) Here the full story:

Yesterday, Valve disabled approximately 20,000 Steam accounts which had been used to try to access Half-Life 2 without purchasing it. The method used was extremely easy for Valve to trace and confirm, and so there is no question that the accounts disabled were used to try and illegally obtain Half-Life 2.

Accounts also may be closed due to fraudulent activity in an attempt to obtain additional products for your Steam Account. This includes Credit Card fraud, theft of accounts you do not own and using cracked versions of Valve games.

If you violate the Steam Subscriber agreement your account can be permanently disabled and you will lose any products registered to those accounts.

Also, a few myths floating around out there that need to be cleared up.

First, Valve did not put out any kind of fake key or fake warez or hack instructions to trap people. The hack came from the "community" as do they all.

Second, the number of people who actually had bought HL2 and used the CD key cheat was VERY small. VERY small. Most people just tried to rip off the game and not bother buying it.

If your account was used by your brother, your cousin, your friend or even your mom and they attempted the hack and now your account is now disabled, you should discuss this with them. If you wish to contact Valve about this issue, visit this support document for instructions.

Also Waldo from the Steam forums posted the following about this:

If you know what 5J52E-FVKXV-882FQ-YJXRQ-DOD98 is for...
...and tried it, please try and refrain from being too upset in your posts.

If you don't know what it was for, it was part of a way to steal HL2 which doesn't work anymore.

If you've got questions about your disabled account, please read the support FAQ My Account is Disabled, Why? for further information.

For more go and check the Steam site.