Quicksort looks significantly better in a functional style. Here's some Haskell, but it certainly doesn't use any Haskell-exclusive features:

    quicksort :: Ord a => [a] -> [a]
    quicksort []     = []
    quicksort (p:xs) = (quicksort lesser) ++ [p] ++ (quicksort greater)
        where
            lesser  = filter (< p) xs
            greater = filter (>= p) xs