I disagree entirely -- "like" is entirely too vague a word. I mean, you like Porcupine Tree, and they're "like" Pink Floyd, right? They're not a "rip-off", by any means (well, except that "Time Flies" is a deliberate rip-off of "Dogs").
I mean, I know what you mean -- certainly, if someone is a Pink Floyd tribute band, they're not bringing anything new to the party, but ... if I were to find a band whose single most audible influence is Pink Floyd, I can think of worse things to be influenced by. (I think we had this conversation the first time we met, so...sorry for repeating myself.)
Oh: Legendary Pink Dots -- they're all over the place, stylistically, so you can't just pick one song, but try the two albums, Crushed Velvet Apocalypse and Maria Dimension and the track, "Premonition 13". I don't think they'll scare you.