Not really a new feature, but one that has somewhat sank into history a bit, is the AVSIM registry of nation flags and your ability to use them in your signature. Here are the easy steps to including your country's flag in your signature.
First, go to the CIA World Fact Book: https://www.cia.gov/library/publications/the-world-factbook/
In the drop down list at the top right of the page, select your country. Let's use Algeria as an example. Once your country's page has loaded, look at the URL in the browser address bar. For our example of Algeria, here is what you would see:
https://www.cia.gov/library/publications/the-world-factbook/geos/ag.html
Note the two letter "ag.hmtl" country list. In this case, AG equal Algeria using the United Nation's approved country abbreviations.
Okay, so then, using the following URL, click on the IMAGE ICON in your signature editor, and input the code for YOUR country in this form:
http://forum.avsim.net/public/style_images/flags/ag.png
This would result in this flag showing in your signature:
Remember to substitute AG with your country's two letter code and keep the ".png" after it.
Mine is:
http://forum.avsim.net/public/style_images/flags/us.png
Which results in this: