I was on the fence between LOTR, Asimov, H2G2, and Earthsea... but of those, only Earthsea has been a real staple at every phase in my life, since I read it before I was even particularly aware of the others' existences. It's not as technical and precisely detailed as Asimov and Tolkien, nor as intentionally humourous as H2G2, but it is emotionally and intellectually evocative, and the themes shift nicely depending on the age of the reader, accommodating many perspectives beyond those I held the first time I read the Earthsea books.

Harry Potter.

I read a ton of LeGuin when I was younger. Not sure how I missed those but I'll definitely have to take a look.

Also I forgot Tad Williams. Both the Memory Sorrow and Thorn trilogy and Otherworld are pretty fantastic IMO. MST was a huge part of my teen years (to the point that I even corresponded with Tad Williams a couple times analyzing the Sithi language.. cos I really /am/ a nerd.)

I love your categories, Al Ciao ibn Highemperor.

Film:

Chronicles of Riddick

You say ha-ha? I say Vin Diesel. You say Vin Diesel isn't part of the setting? I say try to think of Han Solo as a bloke who looks nothing like Harrison Ford.

TV Series:

Firefly

It's all about cowboys in space. Talking about which, for those of you who read, you may want to check out the Space Westerns science fiction magazine.



Comics:

Aliens VS Predators

I've read some very good sci-fi comics, but the sci-fi setting in which Predators are blasting Aliens to bits in a remote corner of the galaxy (courtesy of Weyland-Yutani Corporation) stands unmatched.



Books: Too hard to decide.