MiniDisc is not useless; it's obsolete. There is a key difference. Nothing as multifaceted as a MiniDisc recorder can be said to be useless.
That said, I think that even if Sony had marketed MiniDisc successfully, it would be obsolescent today because its competitors are more feature-rich.
I have difficulty following some of the logic in this thread. MiniDisc and MP3 players both have shuffle functions. It's up to the user whether or not to use them, and absolutely nothing about an MP3 player compels one to do so. It SHOULD go without saying that either is just as capable of playing entire albums chronologically. You're arguing against your perceptions of MP3 users' supposed preferences, which are likely exaggerated and unfounded. The issue was the native functionality of the devices and which better suited the questioner.
I still have my MiniDisc players, though I almost exclusively use my MP3 player (and never on shuffle). I may be returning to reporting soon and thus would use my MiniDisc to record, even though my MP3 player has a voice recorder. I also take out MiniDisc sometimes just for nostalgia.
Whereas many of you are exalting album listening, I actually got into MiniDisc because it facilitated playlists, but now MP3 players do this better because the track need not be re-uploaded to form the playlist. Album listening has its advantages and purposes, but playlists demonstrate the user's creativity and make for great time travel. In my moments of nostalgia, I can call up playlists of the songs that defined eras I miss. It's a beautiful thing.
One of you said you found MP3 players useless because they could not do all the things a MiniDisc player could. That depends on the MP3 player. (Further, it's a bogus statement because any mass storage device that plays music clearly has a twofold desirable purpose.) I actually can edit titles and move files on the go, but let's be honest: It is rare that such an act is of such pressing import that it can't wait until one gets home. My MP3 player is an Archos 5, which, like many MP3 players, has great sound quality, radio, a 250-gigabyte hard drive, a voice recorder, Wi-FI, Web radio and TV, DVR, picture display, and video. Useless because it's an MP3 player? Oh, brother.
Much of this stems from your zeal to vindicate the MiniDisc, which I love. Another example is the citation of an intangible such as "cool factor," which lies in the eye of the beholder. Consider that being in the in-crowd like an Apple user can be said to be cool. Also, cool as in different just means anything opposed to the leading product, and that doesn't necessarily mean a MiniDisc. A lesser-known MP3 player can turn heads, but turning heads is not where the joy in product use lies.
It is also flawed logic to assert that one likes MiniDisc because one prefers to carry around just a few albums. One can choose to listen to just a few on an MP3 player, first of all. The mere presence of all the other tracks you have neatly stored on the hard drive will not weigh heavily on the mind. Second, both MP3 players and MiniDiscs are mass storage devices. That's like one compulsive overeater defaming another because the other is even worse. That does not make you the icon of restraint; rather, you prefer a lesser example of excess.
I do believe there still are real advantages to MiniDisc that relate to its native functionality. It's durable, sounds great, and records. It edges out MP3 in battery life, line-in recording, and usually voice recording. Actually, recording is where its greatest strength is now. Another strength is that different models are tailored to different uses; some have radio, some record and others have a digital amplifier, for instance.
I love that my MP3 player works with Windows Media Player, which keeps track of the tracks you have and have not added to the device. Syncing automatically adds the new tracks. If I went back to MinDisc, I'd have to guess where I left off as I tried to upload all the music I have purchased since then to MiniDiscs. Also, I don't have to be bothered with SonicStage or ATRAC anymore, and I am glad. I don't have a second-generation Hi-MD player, so I can't put MP3s on them.