There's a Kickstarter going on right now for a product called the DudeRobe, which is a bathrobe that's disguised as a hoodie and sweatpants. The insides are lined with that sweet bathrobe towel material you love.
If you want them, it's $54 for the pants, $64 for the hoodie, or $114 for both. They're scheduled to ship in October.
More info at (Kickstarter)