5. Other SEO tools

Here is my full listing of different types of SEO tools

1. Keyphrase analysis tools (for SEO and also PPC)
2. Keyword Density Tools for SEO
3. Backlink or inbound link tracking tools

• Yahoo Site Explorer - this is an excellent backlink checker.

1. Robot Crawling tools for SEO
2. Index inclusion tools for SEO

• See my post on Index inclusion tools

1. Reputation management tools

Mainly PPC Analysis tools

1. Bid management tool in particular its capability to manage a portfolio of keywords against different targets of conversions, CPA, revenue etc and also any requirements for page tagging or third-party cookies.

Both SEO and PPC Analysis tools

1. Keyphrase management tool / repository
2. Keyword ranking tools - for SEO mainly but can do PPC
3. Standard Web Analytics tools

Simpler analytics conversion tracking tools