I have found the MIT Open Courseware to be a great resource for free computer science college courses. Every software engineer should be required to take the Structure and Interpretation of Computer Programs class. Berkeley and Carnegie Mellon also provide some great online courses. Are there any more colleges that offer quality computer science courses?
Stanford offers some of their courses online, at http://scpd.stanford.edu/ A few of the seminars are free, but most are not.
Before Internet delivery became viable Stanford offered courses via closed circuit television to video conference rooms in a number of Silicon Valley companies. Most of the Computer Science faculty are quite comfortable presenting courses to students who are not physically present in the room.
I am of the opinion that if its free then the certificate/diploma/degree is not worth the paper it is written on. I would put this sort of thing in the same category as internet ordinations.
But that does not mean there are not good distance education programs out there that deliver content via the internet, I did a few courses with The Open University and found them to be very well organized for delivery over the internet. These guys have been in the distance learning game since 1969.
To tack onto Denton's answer, Stanford offers a bunch of their courses in podcast form. http://itunes.stanford.edu/
There are a number of CS podcasts in the "Science and Technology" section.
It's also worth looking on iTunesU, as there are several courses on there (including, but not limited to ones from UC Berkeley).
I did not mean to imply that the courses should be taken for credit or certification, but only for my personal enrichment. For instance, I get more out of the MIT Artificial Intelligence online lectures and the book than simply just reading the book. Some of the supplemental materials offered with these courses further solidify the teachings.
The MIT Open Courses are good, but the quality and completeness of courses are very uneven.
My favorite is 6.033 Computer System Engineering, which has videos of most lectures. (Something most don't have, unfortunately)
It's worth mentioning that the MIT math department has some excellent Open Courses for computer science folks with full video lectures. 18.06 Linear Algebra is fantastic.
See SEE (Stanford Engineering Everywhere). Programming courses are: Methodology, Abstractions, and Paradigms. There's also some AI and Applied Math.
The Stanford Engineering Everywhere course called Programming Methodology is great. The professor is smart, teaches well, and has a sense of humor. The videos are available on iTunes or YouTube, and all of the handouts/tests are on the SEE site.
I did run into a problem with the iTunes videos, though. They would sync to my iPod (5.5G), but they wouldn't play. I had to reconvert all of them, a painstaking task for my little Celeron.
I'd suggest ArsDigita, especially the Theory of Computation courses, which as far as I'm concerned, can't be beat if you are interested in Compilers/FSM's/Turning Machines.
Academic Earth has free academic video courses from leading universities.
The Structure and Interpretation of Computer Programs
Berkeley / Computer Science
Brian Harvey
Data Structures
Berkeley / Computer Science
Paul Hilfinger
Operating Systems and System Programming
Berkeley / Computer Science
John Kubiatowicz
Computer Science I: Programming Methodology
Stanford / Advanced Placement (AP) Test Prep
Mehran Sahami
Computer Science II: Programming Abstractions
Stanford / Advanced Placement (AP) Test Prep
Julie Zelenski
Computer Science III: Programming Paradigms
Stanford / Computer Science
Jerry Cain
Machine Learning
Stanford / Computer Science
Andrew Ng
Introduction to Computer Science I
Harvard / Computer Science
David J. Malan
Understanding Computers and the Internet
Harvard / Computer Science
David J. Malan
Introduction to Algorithms
MIT / Computer Science
Charles E. Leiserson
VideoLectures.Net. Description:
VideoLectures.Net is a free and open access educational video lectures repository. The lectures are given by distinguished scholars and scientists at the most important and prominent events like conferences, summer schools, workshops and science promotional events from many fields of Science.
I just found a good resource:
Harvard CS-75 - Building Dynamic Websites
A previous version is also on iTunes.
On the site, they have full transcript of the lectures (!), slides, sample code in various formats, videos of the sessions with TA's, etc. It's the richest source I've found. There are a couple other classes too, including CS-50, intro to comp sci.