This hotel was formerly a residence, built in the 17th century.

It does not claim to be chic or rich in amenities. Some rooms are very small, but warmly done up and all in all, you're not paying very much for a whole lot of atmosphere and a great location. There is no elevator or air-conditioning, but breakfast is included and is set up in the lobby, or it can be had in your room. It's a great deal.
Hotel du Lys
23, rue Serpente
6th Arrondisement
Metro: St. Michel, Odeon
www.hoteldulys.com