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+### About
+
+`stressdrive` is a Mac OS X command-line tool meant to verify correct operation of a drive. It does so by filling a drive up with random data and ensuring all the data can be correctly read back.
+
+It was written to verify correct operation of [de-duping SSDs](http://storagemojo.com/2011/06/27/de-dup-too-much-of-good-thing/), but it be used with normal HDDs or any rewritable block storage device.
+
+**DANGER:** `stressdrive` will overwrite, without warning, all data on the given drive. Be sure to double-check the drive you're aiming it at (Disk Utility.app > Select Drive > Info > Disk Identifier).
+
+### Usage
+
+	sudo ./stressdrive /dev/rdrive1
+
+### Sample Run
+
+	$ sudo ./stressdrive /dev/rdisk1
+	blockSize: 512
+	blockCount: 512000
+	writing random data to /dev/rdisk1
+	writing 100% (block 511360 of 512000)
+	2eed7209b7a5b9a1a22cd4eb1b77a59da23c1d56 <= SHA-1 of written data
+	verifying written data
+	reading 100% (block 510323 of 512000)
+	2eed7209b7a5b9a1a22cd4eb1b77a59da23c1d56 <= SHA-1 of read data
+	SUCCESS
+
+### "How is this better than Disk Utility's 'Zero Out Data'?"
+
+Some SSD's de-duplicate stored blocks. For these "filling" it with zeros if actually just modifying one or two actual mapping blocks over and over again. It's not a real test of the SSD's hardware.
+
+### "How is this better than Disk Utility's '7-Pass Erase'?"
+
+`stressdrive` only overwrites the drive with data once (so it's 7x faster) and then verifies all the data is correctly read back (which Disk Utility doesn't do at all).
+
+### "Pshaw! I could do this with `dd`, `/dev/random` and `shasum`!"
+
+Indeed you could. I prefer a minimal focused tool whose operation is fixed, its source simple+readable and offers good built-in progress reporting.
+
+### Portablity
+
+`stressdrive` should be easily portable to other Unixes if anyone what to do that and toss me a Pull Request.