From the US Postal Service:
You pick the product. We’ll pick up the package.
The Postal Service on Sept. 7, 2014, will expand the range of products eligible for free Package Pickup, which enables customers to request that USPS carriers pick up shipments during regular delivery when the request is made by 2 a.m. CT.
Previously limited to expedited packages, options for free Package Pickup will include First-Class Package Service, First-Class Mail Parcels, First-Class Package Returns and ground products (such as Library Mail, Media Mail and Bound Printed Matter Parcels), as well as any package paid for using the Electronic Verification System or through Click-N-Ship Business Pro, the manifesting tool for small and medium-sized businesses.
Customers can, of course, continue to request pickup of Priority Mail Express, Priority Mail, Global Express Guaranteed, Priority Mail Express International, Priority Mail International and First-Class Package International Service. USPS will also continue to pick up Merchandise Return Service, Parcel Return Service and USPS Return Services items.
If you have questions about these changes, please send an email to firstname.lastname@example.org.