I’ve gathered some links and samples to allow anyone to get started quickly and easily with background agents and alarms/reminders on Windows Phone! Here are they are:
Background Agents Overview for Windows Phone
How to: Implement Background Agents for Windows Phone
Background Agent Best Practices for Windows Phone
Unsupported APIs for Background Agents for Windows Phone
Background Transfer Service in the "Tidy" application
Adding Multitasking to Your Application
http://www.jeffblankenburg.com/2011/11/25/31-days-of-mango-day-25-background-agents/
http://www.jeffblankenburg.com/2011/11/26/31-days-of-mango-day-26-background-file-transfer/
Skydrive folder with samples: https://skydrive.live.com/?sc=documents#cid=10E568ADBB498DC8&id=10E568ADBB498DC8%211668&sc=documents
Dimitris Gkanatsios 