My teaching neighbour, Mrs. Jayne Stevenson shared this great idea and Web 2.0 tool to allow students to post comments and/or answer questions.
Post Edited on April 28, 2011.
Although Wallwisher seems like a great program, there are problems. Students tried repeatedly over the last two days to access the program. After several million error messages, I changed my mind about Wallwisher. The first requirement for any web 2.0 program is reliability. The inability to post makes this program frustrating, and not at all worth using until the glitches are worked out.