Here's an item that might fall under both the frugal and sustainable categories. It's a
power cutter currently on sale at Menards.
For the frugal part, just a couple of years ago, these power cutters cost around $50.00 each. I bought my power cutter from Harbor Freight last year, on sale, with discounts, for just under $25.00. Now, Menards is selling essentially the same power cutter for less than $10.00, on sale, this week!
On the sustainable part, I use my power cutter to cut up all our cardboard boxes into strips to feed into my paper shredder. I use those cardboard shreds to mix in with my coop litter, which is mainly shredded paper for the past couple of years. All those paper and cardboard shreds used as coop litter get cleaned out twice and year and dumped outside into my chicken run composting system, where they break down in compost. I use that compost for my raised bed gardens, growing food for the family.

Previously, I tried cutting cardboard boxes with a big manual scissors, and my old hands starting cramping up after a short while. So, I never bothered trying to repurpose my cardboard at home. We just piled it up until we drove out to the recycle center maybe once a month. Honestly, I don't think much, if any, of that paper and cardboard gets recycled. My bet is that it ends up in a landfill somewhere. Since I got that power cutter, I have been able to cut all our Amazon and QVC shipping boxes into strips to feed into my paper shredders. It's been over a year since I have taken any paper products to the recycle center. Instead, it all now gets shredded as used as coop litter before making it into compost.

I like to think shredding paper and cardboard at home, using it as coop litter, turning it into compost, and then feeding the garden beds which grow food that we eat is a much better use of that "waste" product then pretending to recycle it at the collection center. I could be wrong about the recycling center, but at least I know that 100% of the paper products I shred at home are used for better purposes.
Anyways, if you are interested, here are more details...
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Disclaimer: I purchased my power cutter from Harbor Freight just over a year ago. I use it all the time and it has had no problems. I have not purchased or used this specific power cutter from Menards, but I suspect it's the same Chinese model just rebranded for Menards. For comparison, here is a current listing of the Harbor Freight power cutter that I have...
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