The Sega Dreamcast marked the end of Sega's storied hardware career, but it's revered by hardcore and classic gamers despite its swift demise. The Dreamcast may have been underpowered compared to competitors like the Sony PlayStation 2, Microsoft Xbox, and Nintendo GameCube, but it was far ahead of its time. It was the first console to boast a built-in internet connection, something now considered standard, and it was also first to allow online multiplayer gameplay.
Plus, it was just a weird little system in a lot of ways, especially in its curious memory card: The Visual Memory Unit, or VMU, was actually a self-contained portable system with its own screen, sort of like a beefed-up Tamagotchi. It fit into the controller and could actually be used as a second, private screen during regular gameplay. It was never really exploited that well (my only memory of it is displaying "Rad!" during games of Crazy Taxi), but had lots of potential--privately selecting plays in sports games, for example.
The Dreamcast is pretty outdated now--it's more than a decade old, after all--but if it was made open source shortly after it was cancelled, who knows what developers and hackers could have done with it. We could have seen VoIP internet calling, chat, or media purchasing. We could have seen real games for the weird little memory card. Who knows?
FYI: Regarding the Toshiba Libretto W105 and dual screen computers, you can actually get a taste of what a dual-screen computer is. Try the Acer Iconia (Tablets section on the web page)which was recently launched.
Libretto's a different beast, though, sub-netbook-sized and usable in a book-style orientation (with dual screens, I don't know whether to call that "portrait" or "landscape." :) It certainly would have been interesting to see running Android with a Libretto-specialized UI.
Actually, while Sega never did make the Dreamcast open source, as a game console of its respective generation it was terribly vulnerable to piracy, hacking, and so forth.
Weakpoint for a console maybe, but as a result the Dreamcast's has a very healthy homebrew community that I believe is still alive to this day.
Zune's not dead, at least not in the way you describe it. Apple's release schedule for iPods is practically every 6 months. Microsoft's release schedule for Zune is new hardware every 2 years (and I much prefer this, easier to keep up). Microsoft has stated that the news of Zune's death has been greatly exaggerated. Windows Phone 7 was the Zune hardware (ZuneHD was released 2 years before the release of WP7 - almost to the month) for this round, and Microsoft has publicly stated this.
While Microsoft did state that there were no current plans for additional Zune hardware, how many companies do you know are will to confirm new products 2 years out from their rough release date? ZuneHD wasn't even a rumor 9 months before it was released, and wasn't officially announced until about 6 months out. I'm expecting a similar play for the zHD2 - so I'll be keeping an eye out come march 2012 and saving up for September 2012.
Microsoft just dumped a ton of money into expanding the Zune platform, and has spent the last 10 years pushing into the hardware market - you think they're going to pull out so easily?