I have book concept in mind that I've been thinking about writing - and will try to submit a proposal to Pragmatic Bookshelf publishing by the end of the year.
I installed TestLink 1.7.0 yesterday - and spent a few hours working it. So far - I'm pleased with what I see.
"TestLink is a open source web based TEST MANAGEMENT and test EXECUTION system under the GPL license (i.e. free to use). The tool enables quality assurance teams to create and manage their test cases as well as organize them into test plans. These test plans allow team members to execute test cases and track test results dynamically, generate reports, trace software requirements, prioritize and assign. "