I created a lesson at a work day that was on fractions. Students had to use pattern blocks to determine the fractions. What fraction of a hexagon is a small triangle? What fraction of a large rhombus is a small triangle? Students did the manipulating at their desks while I demonstrated and guided them at the Promethean board. By the end, students were coming up to the board to demonstrate their understanding. I did the lesson several weeks ago, and when we did a review yesterday, students seem to have retained the information well.
Another lesson that I thought went well but wasn't planned ahead of time was one where I used the board to help kids plan a project they were doing on our ecosystems unit. I took all of the required documents they needed and made them into a flipchart. We reviewed, they with highlighters and paper, me with the Promethean highlighter. I then imported all of the pages as .jpg files and put them on our class wiki. I was amazed at the number of students who told me that they accessed the documents online to show their parents or to work on the projects over the weekend. I thought it was very effective to have the exact documents on the wiki that we did in class. It wasn't fancy or pretty, but it seemed to be very effective.