An excellent option
The Babel Hostel is right next to the Central Station Wroclaw. It's backpacker accommodation, with huge shared rooms. Tiny and very friendly, with two bathrooms (you can be waiting a long time for a turn!) and a basic kitchenette where you have free tea and coffee 24 hours a day (and sometimes biscuits for dunking). There's wifi, and the recepcion staff are lovely. I felt almost at home. If you have to catch a train early in the morning, or you arrive late at night, this can be an excellent choice. The city centre is ten minutes walk away, and there are trams nearby.