Janko Nilovic deserves attention. He composed a huge volume of library music in the 1960s and 70s, and what I've heard of his work has all been excellent. Some of it has recently been made available on CD by the Cosmic Sounds label, who are also releasing new work by him. It's hard to sum up his work, because it was quite diverse. From what I've heard, Nilovic was like a jazzier, more wild version of other contemporary library composers like Roger Roger and Nino Nardini.
This is a wonderful instrumental that opens with a bare breakbeat. This is soon joined by bass and electric guitar, which then give way to a Morricone-style harpsichord, which riffs over a descending minor chord sequence. The whole thing remains funky and slightly menacing as different parts drop in and out. The whole piece is really just a simple jam, but the impeccable arrangement takes it to a higher level.