Best way to generate slugs (human-readable IDs) in Rails

You know, like myblog.com/posts/donald-e-knuth.

Should I do this with the built in parameterize method?

What about a plugin? I could imagine a plugin being nice for handling duplicate slugs, etc. Here are some popular Github plugins -- does anyone have any experience with them?

1. http://github.com/rsl/stringex/tree/master
2. http://github.com/norman/friendly_id/tree/master

Basically it seems like slugs are a totally solved problem, and I don't to reinvent the wheel.

I use the following, which will

• translate & --> "and" and @ --> "at"
• doesn't insert an underscore in place of an apostrophe, so "foo's" --> "foos"
• doesn't include double-underscores
• doesn't create slug that begins or ends with an underscore

  def to_slug
    #strip the string
    ret = self.strip

    #blow away apostrophes
    ret.gsub! /['`]/,""

    # @ --> at, and & --> and
    ret.gsub! /\s*@\s*/, " at "
    ret.gsub! /\s*&\s*/, " and "

    #replace all non alphanumeric, underscore or periods with underscore
     ret.gsub! /\s*[^A-Za-z0-9\.\-]\s*/, '_'  

     #convert double underscores to single
     ret.gsub! /_+/,"_"

     #strip off leading/trailing underscore
     ret.gsub! /\A[_\.]+|[_\.]+\z/,""

     ret
  end

so, for example:

>> s = "mom & dad @home!"
=> "mom & dad @home!"
>> s.to_slug
> "mom_and_dad_at_home"