I really enjoyed my experience in Good Bye Lenin Hostel of Grodzka street. I met 3 different persons of the staff, and the 3 of them were very helpful in everything i might need, nice and professional.
I have been surprised that for the price of night (around 35 zlt) i had my bunk bed, breakfast included; a free vodka welcome shot, and internet access (there are two computers). There as well a coffee machine that you can use all day long.
The hostel is very well located, near the main Market Square and in one of the liveliest and busiest street of Krakow. So for girls traveling alone like me, there are no problem in going around in the night, you're in the center of the city.
There is a Polish bar downstairs, but i've not been disturbed by the noise (i'm as well not a picky person about that matter).
I have been staying in a 8 beds and a 6 beds dorms, and each bed has its locker. There are only 2 bathrooms per floor (at least in the floor i stayed at, of 4 rooms) but... more