Los Pireta (the Pirate) in Lajares has free Wifi. They also have some power sockets near tables inside.
Also have great home made food. 3 course lunch with drink and bread €8 Excellent helping, it is a favourite with the local builders etc. So girls if you want to see some builders cracks this is the place.
On our way from the airport we make a call in there for lunch before going to supermarket.