no dress code. I usually wear a Rockets jersey 2 or 3 days out of the week. Usually on the day of a Rockets game.
Mon - Thurs Stiff collared dress shirt, (not polo), slacks (not khakis), dress shoes, some people wear a tie I don't unless we have a board meeting. Friday - polo, jeans, sneakers
I do most of my actual work at home, so I wear whatever, but every once in a while I have to go to a meeting with some executives and the like. At first, I wore a suit or dress shirt, tie and khaki pants or something like that. I was told, though, that my dressing up made the executives uncomfortable (even though every one of them is always dressed in an immaculately tailored suit), so now I go with shorts and a t-shirt.
faded jeans + tshirt + boots + sweatshirt. if the president of the company wears only jeans and polo shirt.... why in hell would i wear slacks and longsleeves shirt.
Business casual M-F. I like wearing a tie once a week to remind myself to take my job seriously. I prefer a formal dress code, though.