[Looking at supersize / extended size clothing which is to say, clothing I can wear. Preferably modeled by fat people.]
They do make some appearances at events, such as the Vegas BBW Bash I attended a few years ago.
I most frequently wear a pink with purple butterflies sweetheart top of theirs. It makes my coworkers smile on the grayest days. I also have a matching purple knit skirt with pockets, which I most often wear on weekends. My floral sundress with black bolero jacket is fine for the office in summer — and great for a party, too.
Big On Batik carries women’s 1x (18/20) – 6x (38/40), and some items in their extended (7X+) sizing. They also offer men’s shirts in XL (53″ chest) – 6X (70″).