What SEO tools do you regularly use?

[carmelmonteverdeinn]

Keyword analysis tools, keyword density tools, index checking, backlink checking, wordprocessor to check spelling and grammar, HTML validation and others.
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banned for faking a signature

[Minx82]

Well I know you got banned and will never see this, but someone else might and it might be helpful. I used the tools at seobook.com.I was sceptical at first but their (free, I haven't paid for premiums) have helped a lot.