Nippaz With Attitude has introduced a Frankie-style "Relax" T-shirt for babies. It comes in sizes 0-6 and 6-12 months, but to get the true, 80's oversized-T look, I say go for the big size.
Just imagine how peaceful discussions of co-sleeping, attachment parenting, and cry-it-out would be if the kids were all wearing these shirts.
Relax t-shirts, £9.99 + 3.50 s/h from the uk [nippaz.com]