Both of these sites offer ideas for choosing the right tool for the task.

This site is a wiki from the College of William and Mary's School of Education. The wiki is brokent down by content area.
http://activitytypes.wmwikis.net/

This is an article that speaks to how to choose the right tool for the task and gives you examples to help guide your thinking...
http://mscofino.edublogs.org/2008/01/19/the-technology-toolbox-choosing-the-right-tool-for-the-task/.