Quest was a cancelled Massive Multiplayer Online (MMO) game that was in development at Rare Ltd. Before Raretopia.com vanished from the web, they had some interesting informations about the project:
When Microsoft purchased RARE, one of the things it highlighted was its established series. Having paid such a high price for the renowned codehouse, Microsoft naturally wanted to exploit its past work to the utmost. Shortly after its acquisition, it therefore organised a restructuring of the company where high-profile franchises such as Perfect Dark and Conker were prioritized over more experimental titles.
The first game to suffer from this change of focus was RARE’s top-secret online game that was originally planned for the Nintendo GameCube but soon converted to the Microsoft Xbox. Codenamed Quest, it was a massively multiplayer online space shooter led by Mark Edmonds, Duncan Botwood, and Chris Seavor in the programming, design, and art roles respectively. Despite having been in the works for about two years, development on the game was progressing slowly, largely due to its lack of distinct direction with regards to design. With the Xbox already being overcrowded with online games, Microsoft thus decided to cancel the title and relocate the 13-strong team to more important titles.
Thanks to Purerarity, some more info were leaked in october 2011:
Quest started around 2000 after Perfect Dark N64 as a mixed fantasy MMO. One name it had for a while was Elements of 3 Powers but it wasn’t related to Kameo (the other team probably took over the name when it was abandoned). Around 2001 Quest was a space shooter for the Gamecube and in 2002 it was converted to the Xbox and shortly thereafter put on hold. After Perfect Dark Zero a fantasy MMO version came back, this time titled Cascade. It was however cancelled in 2007 when the team did GoldenEye 007 for the XBLA instead. As you all know, the latter was finished but never released.
Sadly there are no Quest images or videos available at the moment.