~25-30 km each way, depending on a specific route. (Riding the same shortest route every time is boring. And the shortest is not always the safest.)
About three days a week: Tue, Wed, Thu. Monday is for bringing a fresh load of clothes (and the laptop) to the office, Friday is for taking them back home to launder. Can be done by bike though, when I'm in the mood...

I ride in my cycling attire, i.e. bib and jersey. Nothing commuter-specific, nothing extra on the bike. Everything that I need for work is stashed at the office. I'm lucky though to have a gym with showers in our office building.