Mystery semi-solved. Whilst the domain appears gone, the Open Racer forum and wiki are still online although just a bit (a really big bit) harder to find. Oh and it's still not open source, which is kinda lame.
Meanwhile check out a racing game that is good and exists and Free Software. Like TORCS (solid game, upcoming 1.3.1 release), or Ultimate Stunts (freeform driving fun), or VDrift (potential amazing). There are a few others, but I'd recommend those 3 first. What's your favourite Free Software driving game?
Curiously, also, Open Racer was the name of a dead fork of Tux Racer, which now lives on as Extreme Tux Racer, which itself was a fork of PlanetPenguin Racer, also a dead fork Tux Racer. Fork that. You may be forgiven for thinking that the Tux Racer project is cursed, but fortunately the ETR guys are doing a bit better and the game has landed in Ubuntu. A new physics implementation is in progress, and 0.5 should be around sooner rather than later. See developer discussions for more details.
Leadgolem's Inventory Concept
Scourge Outdoors
Ilya's Inventory Concept
Scourge development has been a hive of activity lately. There's proposals on a new inventory system, lots of optimizating, and in general the game is looking very cool. Does anybody know much about animation systems? Think having a human model and dynamically overlaying parts of armour or clothing and how that would all tie together with animations etc in 3D. If you know about that, contact the Scourge team as they are looking for advice.
There's been a lot of nice new features added to Scourge this year - outdoor areas, cutscenes, new storyline, graphical enhancements galore, and lots of cool models of armour etc. The one bit limitation at the moment is the limitation in model format support, especially character models - currently just md3 is supported. The whole armour-character combination could be a compelling enough reason to see a move to a better format. I like the project a lot and hope to see a few more contributors when such limitations are overcome.
Tikiwiki does suck though. Usability nightmare.
On a related note, Scourge contributor Ilya created a lovely 2d inventory system which won't be used in Scourge but is really nice. Screenshot on the right, more information and images here. If you have an alternative project please suggest because it'd be a shame to see such lovely pixel art go to waste.
Development of netPanzer has been active lately and the current developer is looking for input on the development direction. If you have any affinity for the project, it would be a good time to chime in! Me? I'd love to see single player. I downloaded it... multiplayer only... off. That's a cold and simple truth.