Silk, one of my frequent recommendations for a good digital portfolio tool, has added support for drag and drop editing of your collaborative digital portfolios. Now you can just drag items from one part of your portfolio to another instead deleting an item and then re-uploading it to move it to a different section of your portfolio.

Silk is intended to be a place where you can share collections of materials as well as write text directly into your webpages. Your Silk dashboard provides a place to organize your materials into collections and subcollections. Your collections can include documents, videos, images, charts and graphs, and links to other sites. You can create multiple sites within your free Silk account. Your Silk sites can be public or private. Creating collections on your Silk site can become a collaborative activity by inviting others to be editors or administrators on a site.

Applications for Education
Silk could be a good tool for students to use to create digital portfolios. Teachers could use Silk to create digital collections of information to supplement or replace textbooks for their courses.