You can also use Obrigado/Obrigada as a polite response to someone thanking you. In this case, it means "You're welcome" or "Don't mention it".
Here are some other options:
* Valeu! (informal, like "Thanks!")
* Muito obrigado/Obrigada (formal, like "Thank you very much")
* Agradeço (formal, like "I appreciate it")