My former high school English teacher's husband worked at the University I first went to, so it was a little awkward at first, but they soon both became good friends of mine and I even visited their house and bought them baby gifts for their baby. We still keep in touch and meet up at the mall even somethings. I also have my former drama teacher on facebook. I think it's cool to keep in contact with them and to see what they're like 'outside' the classroom.