Here is a nice “Exchange Scripts” page from Microsoft All-In-One Code Framework.
http://blogs.technet.com/b/onescript/p/exchange.aspx
The All-In-One Script Framework Exchange script samples are based on frequently asked IT tasks that the team observed in TechNet Exchange forums, Microsoft support incidents, and various Windows IT communities. They hope that these customer-driven automation script samples can help Exchange server administrators deal with some typical IT tasks in shorter time.
Here are some of their nice Exchange script samples
Export Distribution Group Members in Microsoft Exchange 2010
Generate report of user mailbox’s size for Exchange 2010
Script to Get Office 365 Mailbox Folder Permissions
Create Report for Average Mailbox Size and Item Count per DB in Exchange 2010
Remove E-Mail address with Specific Domain Name in Microsoft Exchange 2010
Add Proxy Addresses for Recipients by Using a CSV file in Exchange 2010