http://www.bbc.co.uk/radio4/features/torchwood/download/
My opinion, for what it's worth, is that the third is the best and they're all OK.
Next week five nights of the TV show, all that they're airing this year. I have to be out on three evenings, I just hope that my PVR works properly...
Later:
Since posting this I've been told that this link doesn't work outside the UK. Overseas listeners should be able to find them via the BBC iPlayer site for the next couple of days.
There are also apparently somewhat less legit torrents, and they've been posted to alt.binaries.sounds.radio.bbc
