FREE Keyword Tool by adCore

Ranked #1 external keyword tool in both 2012 and 2013, the ultimate Keyword Tool by adCore is a must for all your SEO, PPC, SEM and analytics keyword research. Included in the tool: Google keyword ideas, Google search terms, the ability to generate 1000’s of keywords, add keyword match types, change case, filter results and much more. Register for full access to adCore, the simple, easy to use AdWords PPC Software. Use adCore to manage all your PPC campaigns in AdWords, Yahoo and Bing.

Screenshots from Chrome Web Store