This is nice to hear. I am currently putting something together using Twilio to make it super simple to get local or tool free numbers to use as tracking numbers for print, web and SEM. The numbers forward on to whatever normal business number you would use, but the call information is all tracked and logged. It can also ping Google Analytics for you or ping your own custom page on your server. This way you can know exactly how many calls resulted from a print campaign, or from your website, etc.