People ask so I'll pass it on.
Vodafone Spain offers two packages aimed at tourists. One for 30 days is voice and data. I think about €15. The other one is only data for 90 days also about €15. Both will renew if you have credit on the SIM at the end of the period. Just hand your ID and cash...
This site is run by Ivar at in Santiago de Compostela.
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