WiseStamp - WiseStamp allows you to easily create and implement slick and unique email signatures for your business.
GMass - GMass allows you to easily schedule emails, send out mass emails and mail merge campaigns and more with Gmail! Click here to learn about more features!
NEWOLDSTAMP - Email signature generator
HubSpot Free Email Marketing - Powerful drag and drop email marketing in the HubSpot CRM
Sigstr - Email signature marketing
Quokka (formerly Kryptowire) - The gold standard in SAST, MAST, IAST, and more!