I've used multiple (4-5) velcro straps to hold a crate on. Mind you, I have grocery panniers, and have only used the crate for short trips that I wanted to keep level (e.g. a birthday cake).
If you search the forums, there's been one or two people who have come up with plans for DIY bucket panniers.
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Cars kill 45,000 Americans every year.
This is like losing a war every year, except without the parades.