Collectors come in all types, on a sliding scale of oddity and quirk.
Some collections take up minimal space, others fill paddocks.
Saffron Howden is a collector of letterboxes. Or rather, she collects photographs of unusual mail-keepers from all over Australia.
''I started taking photos of quirky letterboxes about a decade ago when I was covering rural affairs for the Sydney Morning Herald," Ms Howden said.
''I was on a long road trip with a long-suffering photographer in western NSW, I think. And I've carried on ever since."
Over the past 10 years, she has amassed a collection of up to 120 of the country's finest letterboxes.
''I love letterboxes because they say 'home'. They can be such an expression of place, and personality," she said.
Though every letterbox brings joy, Ms Howden's particular favourites are those that are well-planned and site-specific.
''I've seen emu-shaped letterboxes in the bush, frog letterboxes in rainforest, trains, horses, pigs, dogs, fish, trucks and helicopters," Ms Howden said.
"There are letterboxes with gardens on top and ones designed to look like faces and houses.
"I especially love the letterboxes made out of old appliances or farming equipment, like microwaves and ploughs or fridges."
As a lifelong writer, the simple symbolism of the letterbox is something that also appeals to Ms Howden's sense of nostalgia.
''Letterboxes also remind me of how much I love letters," she said.
"Real ones. So few of us sit down and hand write letters these days. It's all done on email and text - even the household bills.''
So come on, show us the best letterboxes you've seen in your travels. Maybe it's even yours!
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