UPDATE 2014-01-14: The attached .zip file now contains a Mathcad Prime 3.0 worksheet (.mcdx) and—for those of you who are still using earlier verisions of Mathcad—an Adobe Acrobat printout (.pdf) of the worksheet so can see how it is put together.
When Mathcad Prime 2.0 came out in 2012 with the Mathcad Prime Express option, I downloaded the program for trial. MP 2.0 wasn't quite where I wanted it to be, so I waited until MP 3.0 came out for "the real thing" (at least for my purposes it's "the real thing"). Even so, I made good use of MP Express for some simple things and overall I like the new design. One of the things I did during downtime over the 2012 holidays to learn MP Express was play around with plotting equations against equations. Since MP Express is limited to XY plots, that's what I played around with. Some of the resulting curves are very interesting and even beautiful.
The purpose of this worksheet is to list my favorite sets and families of equations and to show some example plots. To see the rest of plots, simply make an XY plot and copy an X-axis equation and its corresponding Y-axis equation from one of the tables and paste them into the appropriate placeholders. The possibilites are endless, but my time is not so this is as far as I got. Enjoy.
BTW, this isn't a puzzle or a game, but this seemed to be the best place to post this worksheet.