On the scale of a whole planet, I'd imagine the only worlds without the industrial base are isolated, low-population startup colonies or post-apocalyptic regressed civilizations.
The RPG Stars Without Number (free on RPGNow) posits a level of technology possible only with advanced psionics ... and all the psionicists died in a catastrophic galaxy-wide Scream. Artifacts produced before then are extremely valuable. While I'm not keen on the psionic angle, I like the general idea of technology nobody knows how to produce locally (anymore).
As those who have read my previous threads will remember, I'm fascinated with the idea of an interstellar civilization without FTL. You'd need some sort of pilot for the long centuries between worlds (e.g. an AI, an alien or mutant with near immortality) and a way to keep humans in stasis for that long. (Generation ships require too many resources to be common.) Restricting FTL to certain star systems, groups, or alien species is a limited version of "no FTL". So is Ursula K. LeGuin's universe in which allows FTL communication but not physical FTL travel (for living creatures, at least): technology and basic knowledge remains up to date, but inhabitants of each planet might differ wildly from human cultural and biological norms.
Now I really want to develop a universe where humans travel FTL only in Mi-Go brain cylinders ... (Or a software equivalent, a la Accelerando.)
Last edited by fmitchell; 01-11-2011 at 11:02 AM.
"On two occasions I have been asked [by members of Parliament], 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question."
- Charles Babbage (1791 - 1871)