A bit of a late reminder, but today is the last day that you’ll be able to play your original Xbox games online, because as of midnight tonight (April 14th), Microsoft will be shutting down support for Xbox LIVE via the original Xbox.

This effectively means that Halo 2, including a bunch of other popular original Xbox titles, will no longer be playable online, either through the Xbox or even the Xbox 360. This change is being made ostensibly to “allow [Microsoft] to continue evolving the LIVE service with new features and experiences that fully harness the power of Xbox 360 and the Xbox LIVE community.”

We’re assured that the decision to discontinue the service was not taken lightly, “but after careful consideration and review [Microsoft realised] that this decision will allow [it] unprecedented flexibility for future features.”

You can read the original open letter from Xbox LIVE general manager Marc Whitten regarding the decision over here.

Also, Major Nelson has a nice timer sitting on the left of his blog ticking down to the eventual closure of the original Xbox LIVE service (now sitting at 20 hours to go as of writing).