Can I use a check_box to implement a date related search? (i.e. show only expired accounts)

[theSociableme]

This works fine, however I want to use it as a check box

 <%= f.text_field :user_profile_expiration_lt, :value => Date.today.to_s(:long) %>

if checked then result set contains only where results with expiration less then today.

i.e. Show only expired []

Any ideas how to do this?
or implement a named scope based off of check_box ?

[graywh]

Use a scope.

class Model < ActiveRecord::Base
  scope :expired, lambda { where(['user_profile_expiration_lt < ?', Date.today]) }
  search_methods :expired
end

<%= f.check_box :expired %>

[gamov]

I've just been hit by a bug using this method @graywh, if I declare my scope with a lambda, I get the following error:
wrong number of arguments (1 for 0) for scope :with_qty, lambda { where(:id.lt => 100) }
If I remove the lambda, it works: scope :with_qty, where(:id.lt => 100)

To make it work, I need to painfully add a management of the checkbox value, this way:
scope :with_qty, lambda { |cb| cb == '1' ? where(:id.lt => 100) : scoped}
which makes me change all my scopes to manage the checkbox version... very ugly.