A CULT would be all right. I could handle being a cult: living hearts torn out of beautiful young virgins, students whipping each other into hysteria repeating my catch-phrases - anything short of mass suicides would be OK, as long as there was some uncritical adulation involved. Or I'd settle for cash.

One reason for switching on The Guide to 20 Years' Hitch-Hiking (R4, Thursday) was the hope that Douglas Adams might have some ideas to share on how to go about creating a cult. The other reason was sheer nostalgia for the original radio version of The Hitch-Hiker's Guide to the Galaxy, which, after two decades and acres of repetition, still sounds astonishingly sharp, fresh and funny. Where the computer graphics of the TV series started to look dated even as it hit the screen, Paddy Kingsland's electronic sound-world retains its air of ambition and inventiveness.

Adams didn't have any hints, of course, just a few remarks that swung between blushing self-regard and self-centred modesty ("Sometimes", he said at one point, "it's hell being me"). If one theme did emerge, it was how infinitely improbable it was that the series was ever made at all. Not only was there Adams's own dilatoriness to cope with (on occasion he didn't finish a script until the actors had all gone home), there was also the BBC's mulish bureaucracy: it was taken as gospel, for instance, that no comedy could be recorded in stereo, since the listener would not know from which speaker to expect the punchline.

If you have any doubts about the influence of Hitch-Hiker, though, try Paradise Lost in Cyberspace (R4, Tuesday). It is tempting to put this future-shock comedy down as one of the BBC's current splurge of rehashed old ideas. But Colin Swash's take-off of Logan's Run is full of ingenious ideas and witty, mildly unnerving extensions of present-day logic (such as a vision of the BBC in the 31st century "broadcasting round-the-clock news to a bossa nova beat").

All the same, it clearly could not have existed without Hitch-Hiker's Guide, as the casting of Stephen Moore (Marvin, the Paranoid Android) and Geoffrey McGivern (Ford Prefect) tacitly acknowledges. That's the trouble with the modern BBC: a programme can be sold as "another Hitch- Hiker's Guide"; but as for a real Hitch-Hiker's Guide, a programme without any precedent - well, "infinitely improbable" starts to sound optimistic.