I recently got a sale catalog in the mail from The Great Courses. My local library has a few of these available for take out, so this was the impetus I needed to actually check them out for preview to see if they were something I was interested in purchasing for my children. I checked out two: The Foundations of Western Civilization and A History of European Art.
My children and I watched one lesson of each just to try them out. They did not appreciate The Foundations of Western Civilization. It was straight lecture with an occasional map thrown in. At 11 and 9 1/2, this is not their idea of a stimulating lesson. A History of European Art fared better. Being as it is art, it featured lots of illustrations and the lecture was explaining them, so all was well! I have ordered that one for school next year, along with The Secrets of Mental Math as a "fun class" for my younger son.
I can definitely see many of these courses being wonderful for high-school aged homeschoolers, however. There are a wide variety of courses taught by some of the best college professors in the country. The courses come with a suggested reading list along with a money-back guarantee if you are not satisfied and free replacement if a disk gets ruined. They are pricey normally (although certainly less than actually taking the course at a college), but right now the sale prices are very reasonable. If you use the coupon code TVF4 (good through April 1st), you can get free shipping as well. Check out their full listing of courses here: Great Courses