BBC News and Slashdot are reporting that the BBC Domesday project has been 'saved for posterity' by emulation.
I worked at the Interactive Television Unit (the BBC department that was founded for the Domesday Project) for the last 3 months of its existence in 1989 before it was spun out into the MultiMedia Corporation in Jan 1990 (I then worked at MMC until 1997, when it became a shell company owned by the stockbrokers, but that's another story).
When we left the BBC, they had all the original video data on Broadcast quality masters, and all the digital data preserved on VAX tapes. They must have thrown those out in the intervening 12 years (which wouldn't surprise me).
I know of two former MMC directors who have CD-ROM backups of the digital data and working Domesday systems.
Which is not to decry the work in emulating it - that is the real long-term answer. This is the technical (as oppossed to the economic) reason why DRM is futile. The Church-Turing thesis (that any universal computer can emulate any other one), when combined with Moore's law (that Computer power doubles every 18 months) means that we will always be able to run old software in emulation. The corollary is that emulation is often the best solution, even compared to recompilation of the original source. As I've said before, MAME is the most impressive example of this truth, though the 68000 emulator running inside the 'Classic' emulator on OS X is another worthy example.