These are my favorites not only for design but also for performance:

Nikon F2 titanium (once owned two)
Olympus OM1 (never owned)
Canon F1 (never owned)
Leica MP-6 (never owned)
Pentax Spotmatic (still own three)

http://www.flickr.com/photos/11336821@N00/5616852552/
http://www.flickr.com/photos/11336821@N00/5226987647/