16 node FreeBSD -based cluster that cost less than $2500.
This is a TV "recorder" consisting of:
Some form of display controller, used to display system messages and menus as well as TV broadcasts,
A disk drive, which can record, in "low quality" mode, 1h/GB, which is used to "record/buffer" programs,
A modem, used daily to connect to a server at Tivo to download broadcast schedule information, and
A PPC CPU, used to control all of the above.
It isn't particularly visible, but the TiVo runs Linux .
Various people have taken interest in trying to expand the capabilities of their TiVo recorders, particularly to allow additional storage.
... To do interesting things like upgrading the hard drive, run other software on the unit, or such...
Tivo units use PPC, not IA-32;
The partition tables on hard disks use modified Macintosh-style partition tables;
The units load a special kernel module in that read/write the special "Tivo" filesystem;
Drives are byteswapped.
With some hacking around, you can mount some of the partitions as ext2 filesystems, and look at the contents of /var as well as root partitions.
Apparently they have figured out how to "bless" a drive so that it can be used to augment the space available.
The TiVo by default uses UUnet as a "local" dial-up ISP to pull schedule information; adding Ethernet would (at least in theory!) permit using a cable modem or DSL connection for this, thus leaving the phone line for phone calls, and providing faster data transfers.
The "Blue Sky" idea would be to take recorded programs, transform them into "blobs of data" in some form, and push them via Ethernet over to secondary storage, thus allowing one to put together a "virtual 240 hour TiVo." Not There Yet...
Freevo is an open-source digital video jukebox (PVR, DVR) based on Linux in addition to a number of open-source audio/video tools. MPlayer is used to play audio and video files. MPlayer is an excellent media player that can play most popular file formats. Freevo can be used both for a standalone PVR computer with a TV+remote, as well as on a regular desktop computer using the monitor and keyboard.
kdetv is a KDE application that allows you to watch television on your GNU/Linux box running KDE. You probably know it as QtVision, the completely rewritten version of KWinTV.
This was to be a $300 USD game console using Linux as the underlying OS. They were unable to get funding to continue development (likely due to the "giant tech stock meltdown of 2001"), so the project did not proceed to completion.
A "lab" in Portland, Oregon that works on system integration efforts surrounding the use of Linux for what are termed "carrier class" systems; these are systems that generally involve large numbers of CPUs and disks, with considerable support for redundancy.