Postman

A postman was a person whose job was to deliver mail.

A postman arrived at the house of Carys Fletcher, who was possessed by Sex Gas. She tried to have sex with him but was stopped by Torchwood Three. (TV: Day One)

In the Dream Lord's dreamworld of 2015 Leadworth, the Eleventh Doctor, Amy Pond, and Rory Williams confronted the Eknodine, one of whom killed a passing postman. (TV: Amy's Choice)

In 2050, a postman named Patrick (as Starkey noted, similar to the famous children's character Postman Pat) was kidnapped by the Centuripede. He was later rescued by K9 Mark 2 and his team. (TV: The Last Oak Tree)

In the 22nd century, after another tremor shook the factory, Buzzer remarked that he should've been a postman like his dad. (TV: The Almost People)

Graham O'Brien, upon reacting to a Kerb!am Man, remarked "Space postman, I've seen it all now." (TV: Kerblam!)

Behind the scenes

 * A specially filmed trailer aired before the premiere of Series 3 of The Sarah Jane Adventures featured Sarah Jane Smith and the gang coming across an postman with an old lady and a teenage girl, one of the three being a Blathereen in disguise. The viewer, having been given the sonic lipstick by Sarah Jane, had to choose which one they believed to be the Blathereen. The correct answer was later revealed to be the postman.
 * David Tennant appeared as a minor antagonist in the 2014 film, Postman Pat, which was based on the aforementioned children’s character.