[TOP TIP] Image to embed
Save the following as img2embed and make it executable (chmod +x img2embed)
Execute the script and give it the filename of the image as a parameter:
$ img2embed linode_logo_white.png data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAHMAAAAtCAYAAA...
The script is pretty basic, it does not do any checking about the input file, so if you want you can add that functionality yourself.