Now days, you can have an integration between Google Calendar, Google Docs, Google Sites and other Google Apps. Therefore, you can have a sense to create a document and to make collaboration with other group members or to create a calendar and to share with any of your groups.
In such a way, Google blog has announced an integration that is available already, for an example, if you are going to organize a local intramural softball team tournaments, you can use Google Docs to keep track of the rosters for each team and the performance of the each team. Moreover, you want all the players, but few of them might have editing access.

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Already, if you have a Google Group set up with the tournaments participants you can simply share the spreadsheet with the group itself and will grant the group members permissions to edit. In order to share a document, a calendar, or a site, you should use the group’s email address in the sharing dialog box. Moreover, if you want to unsubscribe from a group, Gmail can make it easier by just adding an “Unsubsribe” option when you click on “Show Options”.

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