CCTF by N/A
A huge pack of textures, containing everything from liquids, to lights, doors, concrete, walls, signs, glass, wood, xen, etc.
Contains 173 textures.
Doom by id Software
Textures from id Software's Doom (1993) and Doom II: Hell on Earth (1994).
Contains 673 textures.
Quake II by id Software
Textures from id Software's Quake II (1997).
Contains 1536 textures.
wad:evil7:dismal-solace by evil lair
Quake 3: Arena style texture set in a gothic/metal theme.
Contains 62 textures.