A great tool I found is the Rapid Reporter. Unfortunately it only works on Windows.
When I was working on a client project we had to do our testing on Windows machines as well as Mac and mobile devices. Rapid Reporter did not work here. So we decided to simply use an Excell spreadsheet for non Windows based testing that pretty much works the same way as the Rapid Reporter. We just keep the spreadsheet open – whether on the same machine or a second one – to create our tests on the fly and also instantly write the report.
The spreadsheet we came up with can be downloaded here. Feel free to use it and modify it the way it works best for you.