Of course, in the early days of the tuxedo (certainly from 1915) the alternative colour was 'midnight blue'.

Midnight blue is an alternative to black as a colour for dinner jackets. Due to the deepness of the colour, midnight blue formal clothes are almost indistinguishable from black. This has been the case since the 1930s, when the Duke of Windsor popularized the colour in suits and tuxedos.
http://en.wikipedia.org/wiki/Midnight_blue

You can still see a few on occasion - usually double-breasted.

Regards

Chas