Was walking through Kmart yesterday and stumbled upon some light weight t-shirts for cheap. They had about 100 left in all different sizes (mostly Medium-XXL) and about 8 different colours/styles.
56% Nylon, 40% polyester, 4% elastine.
$3 with the full price tags priced between $6 and $12 depending on the style.
Bought a few of these at Indooroopilly in QLD a few weeks ago for same price. Great value!