I read about this hostel in the newspaper. It is near the main railroad station and the Cologne Cathedral. They offer from 1 bed rooms to 6 bed rooms with shared or private bathrooms - For a bed in a six bed room they charge 17.- Euro without breakfast - and all the necessities you need travelling with a pack: laundry, kitchen for guests, free Internet and WLAN, breakfast café and bar. The reviews are mixed, some good, some bad. One has to check it. But for a few days it might be okay, specially because of its location.