My very first week here at mental_floss I wrote an article called Periodic Tableware, about how people have taken the periodic table of the elements and adapted the form in interesting ways. Since then, I've run across quite a few more examples. Thanks for the suggestions!
In addition to the previously mentioned State of Kansas Table of Elements, here are a couple more tables used to make political points for science. The Cobb County Table of Elements was created by Loren Williams (who also created the Kansas table) in reference to the Cobb County (Georgia) school board decision in 2002 to place warning stickers on biology texts. The decision was recinded in 2006.
The A to Z Guide to Political Interference in Science has categorized their material several ways, including an interactive periodic table. Click on each "element" to read more on a particular subject.
More periodic tables, and less seriousness, after the jump.
Wellington Grey produced the Periodic Table of the Internet, with "elements" sorted into categories such as search engines, webcomics, blogs, and social networking. mental_floss will be there someday.
Although the Periodic Table of Candy is arranged in alphabetical order (from Atomic Fireballs to Zotz Sours), the groupings seem to make some kind of sense.
The Periodic Table of Mathematicians has the original symbols for the elements, but click on each and you'll find the biography of a famous mathematician whose name contains those letters!
Pugsly's Trading Post has several periodic table posters for sale, including charts on vegetables, endangered species, and desserts. (Thanks, Peg!)
Then there are the tables that show the original elements with a difference. The Periodic Table of Elements in the Ocean is an interactive table, with clickable elements. The ones in red have extra information on their distribution and signifigance in ocean studies. (Thanks, Tamara!) Click on each element in the Biochemical Periodic Table to find out how the elements are used in life forms.
Many blocks of the Poetic Table of Elements will lead you to poetry about or inspired by the element. everypoet.com invites you to submit an elemental poem, too!
Periodic tables have been adapted for personal use, too. You can wear a periodic table tie or socks. The Periodic Table Shower Curtain from the mental_floss store can be used as a study aid while spending your time in the bathroom. If you get this to impress your guests, you'll need to be prepared to explain at least a little bit of it!