As Erasmus student or member of ESN you can get ESN card which is very useful. You can find with it many discounts for different things in different countries. Our local section has also local partners. One of them is Stone´s bar, where you can get 20% discount for alcoholic drinks and the other one is called Rekola, which is a system of bike sharing service.
All information about international and Czech discounts you can find on these websites: https://esncard.org