Marrickville social enterprise Reverse Garbage is celebrating 40 years of getting creative with industry waste to support community projects.

Founded by local school teachers wanting to divert landfill to school projects, the cooperative now receives donations by the thousands and last year served 61,000 customers.

Chief executive Dare Kavanagh said it would be impossible to estimate the number of odds and ends held in the 800-square-metre facility.

And with so many items — they recently received a donation of 20,000 table legs — she is continually impressed by the creativity of individuals and groups wanting to recycle.

"It's really a matter of reusing and repurposing things," Ms Kavanagh told 702 ABC Sydney.

Dare Kavanagh says the social objectives of the cooperative are unchanged after 40 years. ( Supplied: Reverse Garbage )

"One of the most common things are the giant rolls of paper, which are very popular with lots of people for an incredible range of purposes.

"Customers send us back photos, which we're always encouraging, with things they've done."

About 60 per cent of Reverse Garbage customers are buying resources for community projects.

"We've got all of these small community projects who are paying a lot for fabric and props and then other groups who are throwing them away," Ms Kavanagh said.

"The social objectives and environmental objectives have been throughout the organisation from the very start."

Speed of technology creates new wave of waste

The nature of rubbish has changed significantly over the years, she said.

The speed of technological change has influenced the donations received by the social enterprise. ( Supplied: Reverse Garbage )

"Our focus on industrial waste remains strong — it's mostly things that come from business, either commercial or factories and industrial-type business," she said.

"But the kinds of things that those factories and businesses are giving us has changed a lot.

"With the speed of technological change, we get a lot of last year's mobile phone covers."

As a sign of the times, Reverse Garbage will be unveiling a large-scale artwork made from mobile phone covers at its anniversary celebration.