I don't have much experience working with multiple colors when knitting, but Helene Magnussen's work caught my eye. She has written a book and patterns using the Icelandic Intarsia technique, I would like to try the Diamond Rose brooches.
(That's her image, used with permission.) Aren't they great? There is a free tutorial on her site for how to do this intarsia technique, worked in garter stitch. I think because these are small buttons or brooches, it would be an approachable way for me to try something new.
Helene is involved with the new e-zine, Knitting Iceland. I am tempted by the lovely free pattern for Freja, and she sells the yarn kits too- hmmmm. I have always wanted to try Lopi yarn. Looks like a cozy and simple winter cardigan!