Before I started building my Dwarf army for Warhammer Fantasy, back in college I started building a T'au army for Warhammer 40,000. I have a lot of it built and painted, but only played it once. I played them against a Chaos Space Marines army and was steamrolled with little hope of survival. It was my very first game, and the opposing player was more concerned about stomping me than teaching me how to play. That was my first and last game of 40k. But I hold no ill will, these were fun to build. Since it was my first army, a lot of the painting is pretty shameful, and several of the pieces are broken over years of storage, but here are a few of my better turn-outs. I may have to dig through and find more to show.
I already showcased some of this army, in the form of the Lizardmen Kroot.