Comment by angadsg

Stack Overflow newsletters[1] are great as well. It sends you top questions of the week, both answered and unanswered. Great way to learn small things about things you love. Its the perfect application of "Knowledge should be bite-sized".

I subscribe to RPi, Net Eng, CS, theoretical CS and Code Golf news letters. Any other suggestions?

http://stackexchange.com/newsletters

edit: Added link