get_iplayer
Evil Penguin-Shagging Communists™ might prefer "get_iplayer" (which grabs stuff from the BBC's iPlayer; pretending to be an iphone if there's an iPhone version, otherwise just grabbing the RTMP stream of the Flash version) and "ffmpeg". Can then convert things to DVD-friendly format, if required, and burn them to disc -- or copy them over to a HDD media player.
http://linuxcentre.net/get_iplayer/packages/get_iplayer-current.tar.gz
http://sourceforge.net/projects/rtmpdump/ (needs libboost-dev)
http://ffmpeg.mplayerhq.hu/download.html
All this stuff is Open Source, and so ought to run even on an AppleTV -- assuming gcc's been ported to it.
@ Tim Parker:
"Component" video nowadays means YUV. Though the plugs are coded green, blue and red, they are not carrying the red, green and blue components that a SCART connector expects; rather, the green plug is carrying the Y signal (= 0.6 * G + 0.3 * R + 0.1 * B + timing pulses), the blue plug is carrying the U signal (= B - Y) and the red plug is carrying the V signal (= R - Y). Getting back the original RGB signals requires a bunch of op-amps and resistors (and before ICs, it would have required at least three valves).
All this was done, historically, for broadcasting purposes, so as to be compatible with existing mono receivers (although in the end, we ended up abandoning any attempt to squeeze colour into the old 405-line system and introduced a brand new 625-line system for colour broadcasting, so perhaps we needn't have bothered). The Y signal just looks like a mono picture. The U and V signals don't need as much bandwidth as Y, since the human eye actually has poor colour resolution, so they are modulated onto a carrier and added to Y to create a single signal for broadcasting.
The reduced bandwidth requirement still applies to digital storage media, of course. DVD data is natively YUV.