This is a Magento plugin for TaxCloud I wrote back in 2013. It worked on
Magento 1.6 and 1.7 with the TaxCloud API as of that time. I happened to be
reminded of it recently, so decided to toss it up on Github in case
someone might find it useful.

I don't know if it still works now (June 2015) or not, so use at your own
risk. Hopefully you will find it useful as a starting point. At the time,
the commercial TaxCloud plugin did not yet exist. If it still works, I'd
be interested to know.

The USPS library used by (and distributed with) this module is from
github.com/VinceG/USPS-php-api

License is GPLv2, so if you distribute it you must release any changes you
make. If you, the store owner, modify it for your own use, you are allowed
to keep the changes to yourself. If you are a consultant modifying it for
a customer, you must provide that customer (and preferably, but not
required, the public) the source code of this extension.