How are blogfolios different from e-Portfolios? They aren't exactly, they're more of a subset of e-Portfolios, or another way of looking at the traditional e-Portfolio.
Though it may seem like everything has an RSS feed nowadays, lots of sites still lack the feature. Fortunately, there's Dapper: The Data Mapper, a web service that will take information from a site and package it in the form of your choice.