I haven't seen a list of themes yet, so here goes.
Mind you, I view these things at 16bpp, and I never know what
name a colour has, so don't rely too heavily on me for your information.
Default theme
Background colour: white
Writeup background colour: gold
Writeup bar: black
Special: epicenter functions below search, displays node creator.
Classic theme
Background colour: white
Writeup background colour: black
Writeup bar: blue
E2 Jukka theme
Background colour: white
Writeup background colour: white
Writeup bar: none
Special: icons on nodelets, recommended
Classic theme goth
Background colour: black
Writeup background colour: grey
Writeup bar: purple(-ish)
Classic theme water
Background colour: purple(-ish)
Writeup background colour: beige
Writeup bar: same as background colour
Classic theme wired
Background colour: yellow
Writeup background colour: pink
Writeup bar: blue
Classic theme charred
Background colour: black
Writeup background colour: grey
Writeup bar: deep red
E2 jukka theme dim
Background colour: yellow
Writeup background colour: yellow
Writeup bar: none
Special: icons in nodelets.