Although URL shorteners can be useful, there are other tools that help share sites easily, such as QR codes. I have used QR codes quite a bit in the classroom when students only have access to iPads. I create my QR codes at QR Stuff, mainly because it is easy to use and it offers a variety options for the type of data source you are using. The app, QR Reader, easily allows users to scan the code and be directed to the site. For fun, I added a QR code to the table in my craft room. It links to the site with the building plans.
Recently, I supported a teacher at one of our sites whose students recorded TEDTalks. At the showcase for parents, we uploaded their videos to Google Drive and created QR codes to make it easy for guests to view them on their own devices.