You can’t go wrong with any of the nature programs, especially if Sir David Attenborough is involved. We’re also into the space/physics programs done by Professor Brian Cox. Make sure you check out the Cosmos series by Carl Sagan, and/or the updated version with Neil deGrasse Tyson. Don’t forget to visit your local museums, observatories, and planetariums.
FYI
Cast Iron Design is now The Office of Ordinary Things. We relocated from Boulder to San Francisco, but otherwise we’re pretty much the same people doing the same things, just a bit more hardcore.