When's the last time you wrote a thank you note...or received one?

Sprint customers shouldn't be surprised if they get one in the mail because the wireless carrier is pushing an initiative in which employees write and send handwritten thank you notes to customers.

The company now has "Thank You Thursdays" in which all employees are asked to write at least five notes that day.

To date, Sprint says it's mailed out more than 470,000 handwritten thank yous.