Follow these steps to unlock Half-Life 2 via Steam and play without a valid cd-key:
1) Launch Steam.
2) Right click on Half-Life 2 in the 'Just Released' list and click 'Purchase'.
3) Enter the following cd-key and click 'Next':
*****-*****-*****-*****-*****
4) When it gets to 2 bars, pull out your network cable or disconnect your modem.
5) Let it keep going, don't crash Steam. When it finishes you should get a message
saying "Servers are busy" and then Half-Life 2 will appear in your 'My Games' list.
Now put the network cable back in or reconnect your modem. Do not attempt to
run the game, if you do, a message will appear saying, "Duplicate cd-key' and the
game will dissapear from your 'My Games' list.
6) Right click Half-Life 2 in the 'My Games' list and click Properties. Change
Automatic Updates to 'Do not Automatically update this game' and then back to
'Always keep this game up to date'.
7) Now you should see a message box saying 'Unlocking Half-Life 2 game files'.
When this is finished (should take between 5-10 mins) Steam will update the game.
8] Wait until the update is finished, and then open the following unencrypted GCF files
using GCFScape and extract all files to 1 directory:
- half-life 2 content.gcf
- source engine.gcf
- source materials.gcf
- source models.gcf
- source sounds.gcf
9) Once this is done, copy your Counter-Strike: Source 'bin' folder and paste it where
you have extraced the Half-Life 2 files.
10) Create a shortcut of hl2.exe on the desktop using the -steam command.
(eg. "C:\HL2\hl2.exe" -steam)
11) Now run the shortcut on the desktop, you should now be able to play Half-Life 2
and WITHOUT running through Steam.
-- Download GCFScape from:
http://countermap.counter-strike.net/Nemesis/
NOTES:
This method might not work with the EMPORiO release, since that release was a pack
of a already installed game. Most likely you'll have to wait till RELOADED or another
game group does the retail of this game so you can put this method to use.
You can stop by #halflife2 in efnet and thank them for this method!