On an automatic signature thingy its "Kind regards" but it depends if the email is asking/telling someone to do something then I change it to "Many thanks" or Cheers if I am more familiar with them.
Pretty much this although I tend to initial stuff if it's informal.
What annoys me is all those email signatures asking you to 'think before printing this email'. I don't need to print it, I already have a place to keep my emails. It's called Outlook.