Columbia University seems to be at the leading edge of online education, at least for an elite university. They were an early participant or founder of Fathom, and offer a variety of enrichment programs as well as a few online graduate degrees.
The oddly-named [url=<a href=“http://www.cvn.columbia.edu/]Columbia”>http://www.cvn.columbia.edu/]Columbia</a> Video Network<a href=“perhaps%20a%20holdover%20from%20a%20previous%20effort?”>/url</a> looks like their most aggressive offering, with a variety of SEAS graduate degrees in Computer Science and engineering disciplines (EE, MechE, etc.). Lectures are distributed over the Web, prof interaction is by email or phone, and exams are locally proctored.
I’m interning at Boeing (aerospace/engineering company) and actually, this same Columbia program came to our site to recruit students. Among all the programs that came to recruit, they were probably the most toughest in terms of academic courseload (Cornell was there too). But their recruiter was probably the most enthusiastic about their program and also showed proof that they were proclaimed the best online program.
Columbia has a great rep (as you know) off-line, so that follows into their distance learning programs. I always recommend this - if you must do a distance program, make sure that it’s from a school that has a great reputation for their “brick and mortar” programs. That way, you’ll get some bang for your buck!