Back in 2008, Murray Siple released a documentary with the National Film Board of Canada called Carts of Darkness. It follows a group of homeless men in Vancouver, British Columbia that found dual uses for shopping carts: a vessel for picking up glass bottles that can be recycled for the money they need to survive and a vehicle for extreme sports.

It sounds wild, and it is, but in Siple’s hands, it actually becomes a fascinating and heartwarming story. Siple had grown up blending sports—including snowboarding and mountain biking—and filmmaking to create his dream career. But a car accident in 1996 left him without the use of his legs; unable to do the sports he loved, Siple also lost interest in film.

Carts of Darkness was his first time getting back into the swing of things in almost a decade. Part of the reason he wanted to make this documentary was because he felt a deep empathy for the men who found their thrills racing shopping carts. All because he decided to say hello to the men he saw dropping off bottles at the recycling center.

“The film is a combination of myself and these characters who are, presumably, homeless and have their issues. But at the same time, we all get a thrill out of extreme sports and the act of having fun being an outsider,” Siple told back in 2008. “There’s a freedom in their lifestyle that I was jealous of. They don’t have the commitments that—I’ll use the word—˜regular’ people do. They don’t have bills, cellphones, and they don’t even have IDs.”

For the men Siple follows in the film, life is made worth it by one long, fast run down the steepest hills in Vancouver. And Siple seems to take comfort in that fact because, with them, he’s not an outsider. He’s just another guy that’s gone through some shit but figured out how to muscle through.

It’s a fascinating look at a genre of extreme sport I never knew existed. The full documentary is available on .