Pifhluk what you are talking about with taking advantage of 0% introductory interest rates is not new, There is a name for it called an App-o-Rama
http://app-o-rama.com/
"The App O Rama is a strategy of completing multiple applications at the same time. The goal is to get as many bonus offers and new credit lines as one desires, in a quick and convenient way."
There have been accounts of people taking out huge lines of credit at 0%, putting it in a long term savings account at 5% and profiting $20,000 after paying the debt back.