Tekeli.li (by RogerBW): Contains all my current role-playing material. Most of it is for GURPS. Specifically:
Improvised Radio Theatre with Dice, a gaming podcast;
Crimson Skies, the alternate-history weird-aircraft setting (campaign writeup)
Dark Conspiracy, the near-future horror setting (campaign writeup)
Horizon's Verge, failed PBEM but contains some spacecraft designs that may be useful
I-Cops, an Infinite Worlds campaign writeup
Last Days of Atlantis, gothic decadent sword-and-sandal campaign writeup
Transhuman Space campaign writup and resources
Tempt Not the Stars space merchant campaign writeup and resources
Weird War II campaign writeup and resources
2300AD GURPS conversions
Shadowrun GURPS conversions
Reign of Steel campaign writeups and resources
This Dim Spot, a not-Aliens-honest campaign (writeup and resources including spacecraft designs)
Age of Aquarius, 1960s psi campaign writeup
Infinite Cabal, campaign journal
Madness Dossier, campaign writeup
Heaven's Dark Hall, campaign writeup and resources