So you think your sip is hip? Wait until you check out the MASON JAR sippy cup. You can buy this at RedRobinRoad for $8. BUT I do think you could DIY this yourself. You can buy the spouts themselves on Amazon. A two pack is only for $8.44! I'm not sure if they'll fit but they look very similar to the one in the photo. They are both from Nuby. Take out the flat circle and replace it with the sippy spout! Voila! Instant hipster sippy cup;-) If you are worried about your kids using a glass cup they do make plastic mason jars. But you might have to cut a hole in the lid yourself for the sippy spout.