You say tank tops are okay at your office? Then nationally syndicated cartoonist Scott Adams isn't a minute too soon with his ninth Dilbert title: Casual Day Has Gone Too Far. This business guru extraordinaire, one of only three strips to appear in more than 1,400 newspapers, has become a major source of comic relief nowadays for anyone who's ever set foot in a cubicle, heard the word downsizing or, indeed, held a day-to-day job in the corporate world. Casual Day, published last month by Andrews &McMeel with a 500,000-copy first printing, settles in for its second week on PW's trade paperback list (Dilbert's previous outing, Fugitive from the Cubicle Police, spent 14 weeks on the list and HarperBusiness's The Dilbert Principle enjoyed a 39-week hardcover run). The total Dilbert oeuvre has sold more than 3.2 million books--no surprise, then, that Adams gave up his day job in 1995 (he was a Pacific Bell engineer). The humorist notes that he still keeps his finger on the corporate pulse, however, thanks to an Internet site that draws more than 80,000 visitors a day.