I like any music that has been thought about while being created and not just churned out to fill the gaps between the silence.
David Bowie is my number one, not only is his music clever and ageless but comes from a time when artists were free to explore by so many untried means and he was right at the front.
I have to agree with Martin about Steely Dan. The first album I heard was Aja and I was hooked.
There are just too many to list, different bands for different reasons but I'm always looking for my new favourite.
Turntable
Toshiba SR-370/Mission 774/Van Damme cable with MS Starline plugs/Ortofon Quintet Black
CD
Cambridge CXC transport/modified Musical Fidelity X-DAC/modified Musical Fidelity X-10 V3 tube buffer
Network Player
Cambridge NP30
Amplifier
Denon HA-500 head amp/Nakamichi CA-5E pre-amp/Chinese passive RVC/Proton AA-1150 DMC power amp
Speakers
Mordaunt Short Signifer on original factory stands
Cables
Mogami with Rean Neutrik plugs/NVA LS5
Headphones
Sennheiser HD600/Sennheiser HD650/Koss Pro4 AA