Disposing of Data and Erasing Myths
After my dumpster diving video on which I described finding a corporate laptop, I was contacted by several firms specializing in disposing of data-bearing hardware safely. Apparently there are several options. One service will wipe and recondition equipment, making it suitable for resale, returning some of the profits back to the original customer. Another will properly disassemble and recycle materials. Another will crush and obliterate hard drives and entire computers.
I like disassembly and recycling in principal, but it seems like an expensive added tax on equipment lifecycle management. I like the idea of reconditioning and selling equipment even better. That way I can get credit for donating the refurbished equimpmtne to a school or charity, or having it sold and recovering some of the costs.
Here's a good article on why standard disk erasure is good enough. (Thanks Teresa.)

If you think of the process on a large scale-thousands of used and functioning computers stay on the market and often find their way into the hands of those who otherwise may never have access to one. Also, the environmental ramifications of millions of less computers needing to be constructed from raw materials is worth mentioning.
As far as data erasure goes, this http://www.justaskgemalto.com/en/working/tips/selling-or-giving-away-my-computer-it-possible-erase-all-sensitive-data is pretty comprehensive.