All of our AP classes give summer work. The AP science courses probably have the most. They require homework to be submitted weekly, either online or by snail mail. Honors courses have significant summer work as well. Summers in my house have had no vacation time in 8 years now due to the homework. This coming summer will be the first time we can actually take a vacation before my triplets leave for college, and my oldest for graduate school without disrupting the homework flow.
Like other posters, our district has all kids do summer reading - assigned by grade and what English class you have in the fall - more challenging for honors/AP etc. I thought the English work is generally too much - 2 to 4 books, with detailed chapter notes and formal book reports/essays for each.
For APUSH, the kid had to read a biography - chosen from a several page list of approved ones - and write a report about the subject. For AP Econ, she had some summer reading and had to analyze a couple of things - less than a day of work. For AP Art (photo) she had to do a few series of photos over the summer.
I am in favor of summer work - I like to see the kid stay busy and I think its good practice at planning/spacing the work.