Having an early flight from Haneda airport one time, I decided that rather than struggle on the rush hour trains with my baggage, I'd treat myself to a hotel near the airport and a shorter, easier journey. Of the many choices available, I plumped for Rex Inn, close to the station and inexpensive to boot.
It's a very typical capsule hotel; traditionally, they're intended to provide somewhere to sleep for men who've been working late and/or missed their last train home, so that's who the facilities are designed for.
The capsule floors look like the crew quarters on a long-haul spaceship; rows of neatly stacked boxes for sleeping in, with a screen for privacy, and inside the capsule are your adequately comfortable mattress, cover and pillow. You can pay more for a cabin, which gives you a more private space, with a desk and chair next to your capsule.
On the upper floors there are some more facilities, aimed squarely at tired salarymen. There's a cafeteria, with vending machines for snacks and drinks, and food service in the evenings. On the same floor there's a manga library, and a room full of massage chairs, where you can sit reading your manga or watching TV.
Then on the top floor there's the sauna and spa; the sauna was compact but satisfyingly sweaty, and it was nice to relax in the big communal bath. There's a small rest area to cool off between soaks and steams, and a small outdoor bath, which in winter allows you to enjoy the contrast between cold air and hot water.
Kawasaki is a large, populous city, so near the hotel you can find a whole wide range of shops, restaurants, cafes, bars and nightlife. There's little nearby by way of sightseeing, but one impressive sight is Kawasaki Daishi, a large Buddhist temple.