Just added to the Basecamp Extras page: RunMyProcess, which lets you integrate your Basecamp information with other applications without any programming.
Alexandre Lachmann from RunMyProcess offered up a few examples of how you might use it with Basecamp:
For instance, you could: 1. Select a Milestone in Basecamp and post it to Google Calendar. 2. Write a Zoho application to create a todo form accessible via Mobile and transfer it automatically into Basecamp. 3. Connect a Basecamp project to an invoicing application. 4. Export minutes of a meeting from Salesforce as a message in Basecamp.The global idea is to offer integration of Basecamp with another application without any programming: Just design the flow of information and select from our library of connectors the one needed.
The Basecamp Extras page has lots of other tools that integrate with Basecamp too.