My wife & I only check baggage when we absolutely have to, which generally means only on overseas trips (1+ weeks).

I can easily live out of a 22" rollaboard for 5 days. Sometimes I take along a small bottle of Woolite so we can wash clothes in hotel sinks, and I buy souvenir t-shirts en route to minimize luggage earlier in the trip.

RC's suggestion might be a good way for us to send the laundry home. My coworkers (esp. the marketeers) often send things ahead, though usually to a client site rather than to a hotel.