When emailing customers from my Etsy shop, I like to compose emails on a personal level but still remain professional. So I've included this email signature provided by WiseStamp that includes my name, logo and links to other social networking sites that are affiliated with my shop.
It is fully customizable, I'm a simple-sally so mine is on the minimalist side :)
WiseStamp allows you to add social networking icons (with or without text beside them) as well as a widget that includes the latest tweet, blog, even etsy shop item along with your signature!
If you have a gmail account, Google automatically adds it to your menu bar.
They offer tons of features and settings - you can either have your signature automatically show up when you compose and/or reply, as well as have a signature for personal emails and a different for business. So check it out and sign up for a new email signature today!