Well I just had data corruption on my Intel NUC due to a stick of RAM failing. Had I had ECC the fault would most likely have been spotted right away. Instead it dragged on for a few months. Glad I kept multi-month backup sets.

Firefox crashed every now and then, but that's not something which raised any flags with me. Other than that the box seemed just fine. Then one day I couldn't boot anymore as the filesystem had been severely corrupted.

Ran memtest86 and sure enough, a span of addresses invariably generated errors in all tests.