1. Instant Feedback: iChat is an instant messaging application, installed on all Mac computers, that allows you to communicate with others in real time. Don't have an IM account - no problem. iChat comes with a feature called Bonjour messaging. Just open the finder, click on Applications and open iChat, log in and open Bonjour messaging, iChat will find all the people in your network who have also opened up Bonjour messaging. Here are some directions for how to do this: http://www.helponechild.org/help/ichatbonjour.html
2. International Photo Sharing: www.flickr.com is a photo sharing Website where people around the world post and share their photos. This is a great resource for copyright friendly images that you can use for presentations and Website. You can also watch photos as they get posted in real time using www.flickrvision.com. You can view a map of the world in 3D and see photos pop up in real time as they are posted. You have to see it to understand it. Give it a try.