A long time ago, I worked for a company that had a neat in-house utility that did something very simple. It's allowed you to write a file at a size you specify. It would then read that file back and check it for errors. You could write the file to a local disk, a mapped network share, or a UNC path (presuming you had permissions, of course).
Using this utility, I was able to narrow down the source of very intermittent file corruption one day. (Turned out an on-board DRAM module in a RAID produced an occasional memory error.)
I would really, really like to get some utility that performs this same function. I am not asking for the utility this company produced, but rather something that does a similar function.
Edit: I prefer a Windows utility. CLI is fine.