It's arguable that no other personal computer can match the style or the class of the Twentieth Anniversary Macintosh, which prominently features Bose speakers, has a built-in TV and radio tuner, came with a leather CD case and a leather holster for a matching pen and pencil set, and also included the unheard of luxury of a man in a tuxedo coming to your house to deliver, set up, and help you learn how to use this computer. The final product was intended to show off the superiority of Apple's technology and industrial design, something which it still excels at-- the TAM (as the Twentieth Anniversary Macintosh is often abbreviated) was a set piece in Seinfeld and other television series, as well as Children of Men.
The TAM started out as a project code-named Spartacus, headed by none other than the now well-known Jonathan Ive. Apple had experimented with radical-looking designs that are strikingly similar to the final product as far back as 1992, but the small form factor components were too expensive to allow for mass production. The Powerbook 3400, which shares an LCD, keyboard, and trackpad with the TAM, started out at nearly $5,000. Ultimately, the decision was made to sell Spartacus for the twentieth anniversary of Apple Computer's existence, even though there was very little market for a $9,000 computer and the high component cost did not allow for significant price drops without selling for a loss. After a few months of poor sales, the price was dropped to $7,500, then $4,000, then $2,000 and even less through developer channels.
Architecturally, the TAM is a near-copy of a Power Macintosh 6500 with a built-in TV/FM card. 32MB of EDO RAM was standard, and 128MB is the limit. The bus is 50MHz and the processor is a 250MHz PPC 603e. The CD drive is limited to 4X because of its vertical orientation, and the floppy drive is on the right edge of the computer. You can upgrade the processor up to a 500MHz G3 via the L2 cache slot, but that requires you to use the included "fat back", as the normal back doesn't have enough room for any expansion cards to be installed. Even with a G3 upgrade, there is a firmware bug that results in total PRAM corruption if you try to install OS X by any method. The subwoofer-cum-power supply, external from the computer to save space and reduce heat, can develop an annoying buzz which is complicated and even dangerous to fix.
Steve Jobs has said that he hates the TAM, because it represents everything wrong with Apple at that time. That is absolutely the truth: the hardware is beautiful, but it's limited and expensive. It cost Apple a great deal of money; less than 12,000 were sold, and its role as a loss leader didn't entice more people to purchase cheaper Macs with bigger margins. Jobs even rejected Ive's original TAM-like design for the iMac G4, opting instead for a "sunflower" shape. The iMac G5 and current iMac designs are more direct descendants, made practical instead of extravagant. Despite all of its problems, the Twentieth Anniversary Macintosh still stands as the very model of a beautiful computer.
Further reference: How to fix the speaker buzz, Low End Mac entry. Also see the ridiculously expensive Appledesign: The Work of the Apple Industrial Design Group by Paul Kunkel.