If you played GoldenEye during the glory days of the Nintendo 64, this'll make you simultaneously nostalgic and, at the same time, sorta angry.
It was rumoured for quite some time that Rare were working on a remake of GoldenEye for the XBLA (Xbox Live Arcade) on the 360. The story was was that there was a rights dispute between Rare, Nintendo and Danjaq LLC and the whole thing was put on the backburner until it could be sorted out.
Time went on, Rare got bored waiting and decided to push ahead with the Perfect Dark remake instead. No footage of the game was ever released and many just dismissed the whole thing as another rumour.
It turns out, however, that there was a working build of the game and what's more, it had both the original version and a remastered version of the game in it. Much the way Halo: Anniversary allows you to flick between the original version of the game and the updated version as you're playing, the proposed GoldenEye 360 would have had the same option.
As well as this, it also had the multiplayer mode and all the cheats attached. It's an absolute crying shame that this was never released, although there is now the GoldenEye Source 5.0 remake available on PC.
Here's 30 minutes of gameplay to watch and cry over.