Dipity is a Web 2.0 application which allows chronological information to be entered and displayed as a timeline. It can then be shared via a blog or other website. This Wimbledon timeline is an example of one your students could make. Any RSS feed can be used and I'm sure there will be heaps during the Olympics. Stuents could also research Olympic data and enter ... for instance, host countries, records for 100 metres, etc.