ggraph is a new, experimental, feature in pluskit 1.2. It allows you to include create flash graphs based on data stored in a google spreadsheet.
Note that the graph does not work properly in preview mode. It only works if you publish it to your web host -- Sorry about that but the way it works it requires a external datasource -- There is a way (I believe) to preview in place and you can certainly publish it to your local mac, turn on web hosting and view it there.
ggraph uses the fabulous Open Flash Chart Package
For example. Here is a table of rainfall for the last week