I still have one in a drawer. I worked at Nokia at the time. These were awesome phones. But they were deliberately crippled by management that preferred other platforms they had.
So, several devices originally earmarked for Maemo/Meego (the name changed at some point) actually shipped with Symbian instead.
Some fun facts about Maemo:
Shipped in 2006 with the N770. Had a tablet UI based on X and GTK, a mozilla based browser and was based on Debian. You could build your own packages, add your own apt repositories, and people basically built most of Debian from source to run on it. E.g. I had a JVM running on it and a full LAMP stack at some point.
The N800 was for a time the only device that could run Android (dual boot) and basically shared large parts of the kernel with it. Google used this device for early Android testing and probably owes a lot to Nokia engineers contributing patches to the Linux kernel. The first Nexus phone shipped quite late in the Android development process.
Development of Meego saw several strategy changes that ultimately delayed products for a long time. One of those unfortunate decisions was the decision to swap out GTK for QT; effectively retiring all of the user facing UI. That set back the clock by years. And it got slowed down further by a simultaneous attempt to get Symbian on QT as well. That trainwreck of course ended up sucking up all the resources and failed to ultimately deliver the goods. This was in the middle of Nokia's realization that "oh fuck this iphone thing is real; we need a touch screen UI". It killed at least two touch screen platforms that it had before it came to that realization.
Technically, the N800 was running circles around the first iphone in terms of what you could do on it. All it needed was a bit of hardware polish and a phone stack. Early Android had nothing on Meego. Even the UX was clumsy and it was slow and limited as well. But unlike Meego, Google shipped it and supported it and persisted in developing it. Nokia instead threw out the baby with the bathwater betting on several other horses before ultimately walking away from the whole phone business.
Nokia declined to combine a phone stack + SIM card with the N770 and N800 deeming it to risky; they were protecting their deals with operators to basically cripple phones in favor of crappy operating services. E.g. bundling Skype with the n800 was controversial. It even did video calls with Skype. In 2007. The N800 was a tablet before the iphone, ipad or Android were a thing. There was not a lot else in the market at that point. That thing with a phone stack would have been a killer product despite its many limitations.
The N900 and the later N9 were both labelled as developer phones and cut off from any serious marketing effort. The N9 technically was a decent phone but by the time it shipped, the team had been layed off, the platform cancelled and Nokia was endorsing Windows Phone. It also shipped an Android phone around the same time, leaving the ugly job of cancelling that product to Microsoft after the acquisition.
Samsung's Bada is a direct decendent of Meego. It never really gained any market share against Android and it seems Samsung pretty much gave up on it.