Gmail, part of Google Apps for Work supports formatted signatures. Containing, images, rich text and links. This is really easy to create in Gmail for desktop.
- Open Gmail.
- Click the gear in the top right .
- Select Settings.
- Scroll down to the “Signature” section and enter your new signature text in the box. You can format your text using the buttons directly above the text box.
- Click Save Changes at the bottom of the page.
Using the formatting options provided, you can insert images, format the text, add lists and bullets as well as links to web pages.
Images via Google Support.