Not everyone on the internet selling something is a multi million dollar mega site. There are any number of people selling eBooks and similar items from very small operations. Any law implemented like the one discussed here would instantly require online sellers to become (or hire) experts not only in their own local tax codes, but in the tax codes of every other jurisdiction imaginable as well. And once other countries adopt reciprocal legislation, God help the online business that sells something to someone living in Russia or Venezuela.