Virtually everyone will remember the periodic table of elements from their high school or collegiate chemistry class. Lists of metals, gasses and other elements were neatly laid in rows, even color-coded sometimes, in an attempt to make the subject more understandable and engaging.

https://www.msu.edu/~zeluffjo/periodic_table.gif
The Periodic Table concept is a useful way to present data for other purposes as well. It’s laid out somewhat differently than the classic chart above, but I’ve used for many years a chart that demonstrates to investors how unstable asset class returns are from year to year (I actually use a different one, but it’s copyrighted):

http://www.callan.com/research/download/?file=periodic/free/360.pdf
Here’s a similar chart including alternative investments:

From a firm that specializes in commodity investments, we have the following:

http://www.usfunds.com/investor-resources/frank-talk/?i=2155
While it may be of questionable value (probably don’t need any more “talking heads” in the investment business) I’ve found some good resources from this one:

TheReformedBroker.com
As a heavy user of the internet for research, I appreciated this periodic table…

http://www.wellingtongrey.net/miscellanea/archive/2007-06-23--periodic-table-of-the-internet.html
…and while I’m not a big user of social media, this is also helpful:

http://www.rickliebling.com/2009/02/23/the-periodic-table-of-the-social-media-elements/
It goes without saying that I’m a visual communicator, so I found this table particularly cool:

http://www.visual-literacy.org/periodic_table/periodic_table.html#
As my Significant Other is well aware, I have a sweet tooth that must be reckoned with; perhaps this table will prove instructive:

http://www.eblong.com/zarf/periodic/closeup.html
Finally, the periodic table’s been used (commandeered might be more like it) by the humorists at ModernToss.com for their Periodic Table of Swearing (you’ll have to visit their site yourself, this is a PG-rated blog.)
UPDATE, August 29, 2010:
Here’s one that landed in my inbox recently I found particularly amusing – enjoy (hat tip, Ritholtz.com)

Aug 31th
Jump-starting the Engine of Job Growth
Author: Kenn Lamson
Comments: 0
Anyone who’s read our research knows by now that we believe the single most important factor for “turning the economy around” is the creation of private sector jobs. Consumer spending, home prices, pretty much every area of the economy awaits the spark inherent in private sector job growth. Further, the US economy is currently bifurcated between large companies with access to capital and small ones without that lifeline (discussed in our recent quarterly letter, found here). We recently read an essay by Vivek Wadhwa, a “tech entrepreneur, academic, researcher and writer” that furthered that argument and expanded our understanding of the importance start-up companies play in our economy.
The final paragraph of his essay hits the nail on the head: “Simply put, if we are serious about lifting the economy out of its rut, we need to focus all of our energy on helping entrepreneurs. Provide them with the incentives (tax breaks and seed financing); education; and infrastructure. And gear public policy—like patent-protection laws—toward the startups. Let’s not bet on the companies that are too big to fail or too clumsy to innovate.”
Link to the full article:
http://wadhwa.com/blog/2010/08/14/startups-or-behemoths-which-are-we-going-to-bet-on/