If you like Princess M, then you should try Spirited Away, also from Studio Gibly. My favourite Giblo is The cat returns

Other favourites of mine are:
Trigun (scifi comedy)
Ghost in the shell, the movie (sci fi)
Ghost in the shell SAC (Sci fi series prequelling the movie)
Techi Muyo (scifi comedy)

My alltime favourite however is Golden Boy, which as a slapstick comedy making fun of the whole "girls in anime" thing.