Gmail team has launched the much awaited feature in gmail, Now you can create a rich html email signature in gmail with images, links and formatting. Now you can create your own custom email signature without the use of Greasemonkey scripts, browser plugins.
You can now add image to your email signature, change the font color etc and do lot more with full formatting options as shown in the image below.
You can locate the email signature options in your gmail accounts settings, once your are done with all the changes in your gmail email signature, click the button at the bottom center of the page saying Save Changes.
[ Source Official Gmail Blog ]