A little-known HTML trick is that you can embed images in an HTML file using a Base 64 representation of an image. For example, a folder open image can be generated using the following text in an HTML page:

<img src="data:image/png;base64,R0lGODlhEAAQAKL/AP//////AMDAwMDAwICAgICAAAAAAAAAACH5BAEAAAIALAAAAAAQABAAAANFKEpMpjAKAkYYTkJqu2sbII6kSCzApXbqM1VrPLiUWpYGFwBF7/+51ID3KwaHReNrlwS+iM0CTRTtTavSjWHL7W41YE0CADs=" border="0" width="4">

which will display as: 

The width parameter can be used to size the image as desired. Note that the image becomes fuzzy if you use a width that is wider than the original image that you encoded.

There are a number of web-sites that will convert images to the Base 64 representation. This Google search provides a sampling.

To see the above img tag as an actual image and for a discussion of a parameter/macro driven approach see my blog post The getImage macro: embedded images using text strings

Thanks to Don Henderson for sharing this tip on sasCommunity.org.