At the end of 2011 DHH introduced commands, a gem which enables you to run your rake commands and TestUnit tests from within your rails console.
If you are using TestUnit commands removes the need for spork or zeus, since rails booting no longer is the bottleneck in your test runs.
The only problem with commands is that you need to tell it to run the tests manually. AutomatedCommands removes this hurdle, enabling you to receive super-fast responses from your tests again.
Check it out!