Basics don't have to be banal, as evidenced by this Italian-made <a href="http://www.mrporter.com/mens/Designers/Lanvin">Lanvin</a> T-shirt. The soft navy cotton has a gentle lustre and the inky sleeve inserts add a subtle contrast of colour and texture. It's cut in a relaxed fit with side slits and a step hem. Try it over slim denim or sweatpants.