internt

Depending on what you need it for, you could tether your laptop to your mobile phone and just use your roaming data, but that may be slow if you want it for downloading films, etc.

Alternatively, there are lots of deals for 'dongles' (mifi devices) where you can pay per day or per volume of data.

I can't recommend this service, as I've never used it, but this feels like it might be what you're looking for:

https://www.spaininternet.net/rent-wifi-spain/

Hope this helps!