How to do more unit testing
It made me
happy 
"Peace of mind in knowing you're not breaking stuff"
How I did it: I used autotest, part of ZenTest's suite. I started with RSPEC, but I'm now actively using Shoulda as it's built on top of test::unit. I use CruiseControl.rb for continuous integration although I'm looking at integrity
Lessons & tips: Be obstinate about it - once you get disciplined, it becomes second nature
