The only valid measurement of code quality is: WTFs/minute

Now Rails has this nifty rake task called rake notes. You can always see notes for a custom tag by:

~> rake notes:custom ANNOTATION=WTF

But rake notes by default only shows notes for OPTIMIZE, FIXME and TODO The Rakefile for changing those defaults is

# for re-defining the Rake task
# otherwise the previous Rake task is still called
task(:notes).clear

desc "Enumerate all annotations
      (use notes:optimize, :fixme, :todo, :wtf for focus)"
task :notes do
  SourceAnnotationExtractor.enumerate "OPTIMIZE|FIXME|TODO|WTF",
                                      :tag => true
end

namespace :notes do
  task(:wtf).clear
  task :wtf do
    SourceAnnotationExtractor.enumerate "WTF", :tag => true
  end
end

Here we have redefined rake notes. The only gotcha is to remember to clear the old rake task by calling task(:notes).clear

For other customizations eg. search the spec folder also you will have to monkey-patch the SourceAnnotationExtractor class

PS: also check this Stackoverflow thread for some fun picks