I use this bag.

http://www.twowheelgear.com/

It's not the cheapest, but it does it's job well (although I wish it were a little longer for my shirts.) I hate ironing, so I just use two sets of shirts. I keep one set at work while the other is at the laundry mat getting cleaned and ironed. When I bring one load there, I pick up the other. It's right on the way to work and works great.

Chris

PS I also use the following item:

http://www.eaglecreek.com/accessories/packing_folders/

for the more casual days. It works great as well.