A few young, talented players in the Portuguese league right now. Porto have James Rodriguez, who you're probably aware of, and there's also Christian Atsu. He's a very skillful winger, made his debut for Ghana earlier this year.
Benfica also have a couple of very good prospects. Ola John and Rodrigo are the most exciting ones. Rodrigo actually had a spell at Bolton on loan if memory serves me correctly. Wouldn't surprise me to see him called up by Spain over the next couple of years. He's been scoring plenty of goals for their U21s.
Sporting are going through a pretty bad patch at the moment, however their academy is still as strong as ever. This season saw the introduction of B teams in the Portuguese league, and Sporting B were running away with the second tier at one point (they're in second place now). Besides Eric Dier, obviously, other very promising players include Bruma, Esgaio and Diego Rubio. Remember the names people.