Slide rules still commercially available?

[Dave Britten]

My wife's a teacher, and brought up those old EZ Grader special-purpose grading slide rules that teachers always seemed to have. I made her a quick and dirty iPad rendition in Numbers (would have been Lotus, but she doesn't use an LX), and then went hunting around and found they're still commercially available!

http://www.ezgrader.com

Are there any other companies still commercially producing some form of slide rules/cardboard "computers"? I'm guessing they'd all be pretty special-purpose, much like the EZ Grader products.