After a couple of years being spammed by SEO marketers from India (with gmail addresses) claiming to be able to get my site highly ranked in Google using "white hat" techniques, I've finally decided to block all emails coming from India.
Seems like a pretty drastic measure to take but I figured that most folks from India probably shouldn't really have any interest in my websites anyway and prior to the surge of SEO spam, I never had a genuine correspondance regarding my site from anyone in India before.
Looking good so far. No more emails claiming to have a "suggestion for your website" from people who have no idea what my website does but nevertheless are "interested to increase traffic to your website".
Seems to save me a minute or two each day deleting these emails which I can spend on posting a topic to Webmasterworld.
In my day I have blocked Brazil, Hungary, Romania, Russia and China.
If they are bulk emails them you can still report them to their individual email providers but that takes a lot of time. Of course if it is a one-off email with you as the only recipient then it isn't technically regarded as spam.