Half-Life 2 now has official support for Oculus Rift, or at least a beta for it anyway.
Valve programmer Joe Ludwig posted about the update on the official Oculus Rift forums, where he noted, "This port is a bit more raw than TF2 was when it shipped, so we would appreciate hearing about any bugs you find. Just like in TF2 this mode is experimental, so we really want to hear what you think."
To access the headset's beta support, open the properties for Half-Life 2 in Steam, set your command line to "-vr", and opt-in to the SteamPipe beta.
Ludwig noted that there are a few issues with the conversion beta, such as the zoom UI showing up in the middle of the screen instead of on the edges like it's supposed to, and the HUD is otherwise dim and hard to read. These issues will be sorted out in time.
To see Half-Life 2's Oculus Rift support in action, check out this early footage by Youtube user Cymatic Bruce.
Additionally, if you want to watch someone's reaction to immersive digital murdering, Youtube user Vaecon adapted Dishonored to work with the Rift, so check that out below.