This is a little off the original topic, but some Japanese business hotels offer coin-operated laundry washers and dryers for their guests. The chain I'm most familiar with is Toyoko Inn, and each one I've been in has washers and dryers in a nook off the lobby. The Comfort Hotel in Yokohama I stayed in last weekend also has machines. Typical cost is 50 yen for soap, 200 yen for a washer, and 100 yen for 30 minutes of dryer time. I like to travel fairly light, so only take 4-5 days worth of clothes with me. Being able to do laundry for a reasonable rpice in the middle of the trip sure beats the laundry charges at other hotels.