Hostelling International made me actually want to spend more days in Boston! It was built in 2012 and has everything you could want in a hostel! The common areas are great, always clean, and everything is very modern. The bathrooms are spacious and practical, and the rooms have all the necessary amenities. As a bonus, there's a huge shared kitchen with every appliance imaginable that's open all day. They also host activities throughout the week like visits to museums or nights out.