I was just wondering why this feature wasn't included in X from the day one. Ubuntu Xorg maintainer Bryce Harrington recently demonstrated the BulletProof-X feature that is planned for inclusion in Ubuntu 7.10:
This specification describes a new failsafe mode that will be used if X fails to start up. It will be in a reduced (VESA 800x600/256 or VGA 640x480/16) graphics environment running a single application (displayconfig-gtk) for configuring the graphics devices.
The goal of this specification is to eliminate the need for users to need to run apt-get reconfigure on the commandline. That approach is confusing and too technical for many users, so moving away from that will solve a key pain point for users.
This is useful if the user has changed monitors or graphics cards or X failed to detect your hardware. Linux based desktop system getting better and better everyday :)