Personally, I tend to go with:
- Regards (of some sort) - for formal communications
- Cheers/Thanks - if I'm asking for something or otherwise want to be nice
- Just my name - for short emails
I got a newsletter recently where they signed off and added a kiss (i.e. a x) after their name. That's just wrong. I'm also wary of Best anything, Warmest anything and Many anything as it usually sounds disingenuous and you know it came from a pre-defined signature.