Slideshare
From MoodleDocs
Can we embed http://slideshare.net presentations in Moodle?
A quick search of moodle.org suggests it may be bug-tracked?
http://www.googlesyndicatedsearch.com/u/moodle?q=slideshare&sa=Search+this+site&domains=moodle.org&sitesearch=moodle.org
with relevant discussion about how this can be achieved:
http://tracker.moodle.org/browse/MDL-7353