If I was starting off as a student I think the 2 things I would want to be told about are
- bookmarking tools (Delicious, Bibsonomy…); and
- reference managers (EndNote, Zotero…).
Although, Alan Cann has written about the challenges of using such tools in undergraduate
teaching (e.g. http://scienceoftheinvisible.blogspot.com/2010/03/begin-beyond.html).
For the more visually inclined a photo sharing site would also be important (Flickr, Picasa…); maybe video (Vimeo, YouTube…).
On top of that all you need is a word processor to pull selected bits together. Master the WP and move on to a blog or wiki (WordPress, PBWorks…). Blackboard? Less said the better, though some people do like that it is a walled garden.