The Gnome Foundation helped make something that isn't ugly; the Bitstream Vera fonts. Well hinted TrueType that looks good when rendered on-screen, free! Western languages only.
Vera Sans Mono fills the need for a good fixed width sans-serif font; Lucida Console just doesn't cut it. Vera Sans is a decent proportional font but is too wide; I still prefer Arial. Vera Serif looks hideous, but then all serifed fonts look hideous on screen.