I've just been thinking about the afterlife of many games systems and it seems they are following a similar path to that of films. Films we now know as "cult classics" were usually panned and slated on release, and this seems to be very true of games systems too.
Look at the Dreamcast. Those of us who actually bought into the system knew how great it was at the time, but the press panned it and warned people not to buy one (mainly after the complete failure of the Saturn!). But now the system is long dead it is starting to see a revival and an ever increasing fan base.
This is being bolstered now by an emulator that can actually run game images perfectly so that new users can experience the best games from old systems without even owning them (although the experience isn't as good without the controllers), and emulation is the key aspect responsible for the recent popularity and interest in many originally less successful systems. But equally I think fast internet connections and torrent technology has a big part to play too.
The Atari Jaguar, 3D0 and Philips CDi are all systems that failed badly, but they now seem to have big followings among emulation and retro gaming fans.
Any other systems you can think of that failed badly in the marketplace, but are now seeing a revival in their afterlife thanks to emulation and collectors?
One other I can think of that is now more popular than ever, and yet wasn't at the time was the CD32!