Why_test
Perhaps my least favorite part of setting up a new project is getting the tests set up. I start projects infrequently enough (and play with different test frameworks often enough), that I can never remember what goes in the Rakefile for an Rspec test suite vs. one for Riot. If you are using rails, you can often +rake rspec:install+ or whatever to get everything set up. If you aren't using Rails, you have to resort to the googles. Why_test takes the pain out of setting up your tests.
Use
Currently only works on Ruby 1.9.2.
gem install why_test
gem why_test riot