for me, the bike ride IS the workout. i live about 4 miles from work. i am, however, lucky in that my job pays for my gym membership. so i signed up to a gym that's one block from my place of work. in the morning, i shower there and change into my work clothes (jeans and a t-shirt mostly) which i carry with me in a bag. actually, i don't really use the gym for much more than the daily shower. i'm fit from cycling eight miles a day.
i don't carry my laptop in/out every day (occasionally, i carry it in my bag) and tbh, my clothes don't get that wrinkled - anyway i don't wear formal clothing at work. as for carrying things like books in and out, well, you find out what you REALLY need to be carrying around pretty quickly. if there's a need to move a lot of things around on a particular day, i can always use public transport. that said, i have two machines for work, a desktop and a laptop. the laptop often stays at home.