I remember playing with an invoice data in XML sending it via email and opening it in a browser being beautifully shown in all it's visual glory using an XSLT d

I remember playing with an invoice data in XML sending it via email and opening it in a browser being beautifully shown in all it's visual glory using an XSLT directive in just one line at the top of the data file. Absolutely amazing. I wondered all the implications and applications of just transmitting data that knew how to present itself to the user