Khan Academy - Algorithms
They've partnered with Dartmouth college professors Tom Cormen and Devin Balkcom to teach introductory computer science algorithms, including searching, sorting, recursion, and graph theory. Learn with a combination of articles, visualizations, quizzes, and coding challenges.
Coursera - Algorithms, Parts I & II
Created by Princeton University. "This course covers the essential information that every serious programmer needs to know about algorithms and data structures, with emphasis on applications and scientific performance analysis of Java implementations. Part I covers elementary data structures, sorting, and searching algorithms. Part II focuses on graph- and string-processing algorithms."
Problem Solving with Algorithms and Data Structures using Python
An online textbook covering sorting and searching algorithms, and going beyond them to cover tree and graph algorithms.
Computational Fairy Tales
Computational Fairy Tales includes over 70 stories that cover a range of different computer science concepts from introductory programming, to high level CS concepts, to data structures and algorithms, to computational complexity, to practical programming tips. Different stories are written in different levels of detail and abstraction (and thus might be better matches for different audiences).
Wikipedia's List of Algorithms
Ever heard of the Traveling Salesman Problem or the convex hull algorithm? These are among the simpler descriptions you will find at this page of over 100 examples.