CS 473: Useful Resources

Illinois course materials
Lecture notes, lecture videos, slides, lab handouts, homeworks, and exams are available for several past semesters of algorithms classes at Illinois. The TV emoji 📺 indicates classes with freely available lecture videos.
Elsewhere
Over the last decade, it has sadly become much less common for instructors to maintain course materials on the open web. Most instructors (or perhaps more accurately, most universities) either lock their course materials inside walled gardens (“learning management systems”) or simply delete them when the course is over. Here are some useful exceptions. [This needs to be updated.]
MOOCs
Coursera, EdX and Udacity all offer complete algorithms courses, with videos, readings, and automatically graded exercises. By necessity, these courses tend to focus more on implementation and less on proofs and open-ended design than either CS 374 or CS 473. I need to update this list, becuase MOOCs are a moving target.
Free Online Textbooks
Hopefully this list will continue to grow.
Dead Trees
For students who prefer an offline reference made of bleached and stained cellulose, we recommend the following textbooks. The campus bookstore probably doesn't have them, but you can find them cheaper online anyway. And they're all in the library. You remember that big brick building with the coffee shop and the study tables in it? Yeah, believe it or not, they have actual books in the basement!
Review
For review of prerequisite material, we strongly recommend the following online resources. (This stuff is also covered in several dead-tree textbooks, but really, why bother?)
Programming contests
...which (at least at the advanced levels) are really algorithm design contests where you also happen to write some code.
Other
We'll add more links here as we discover them. Suggestions are welcome!