adds ajax to all forms on a page within a div with 'jaxy' class name.

Form class name is the update target.

window.addEvent('domready', function(){

        var forms = $$('.jaxy form');
        forms.each(function(element){

                element.addEvent('submit', function(e) {
                        new Event(e).stop();
                        var url = element.getProperty('action')
                        var rest = element.getProperty('rel')
                        var target = element.getProperty('class')
                        var box = $(target)

                        if (rest == 'delete') {

                        new Ajax(url, {
                                method: 'delete',
                                update: box,
                                onRequest: function(){ 
                                  box.addClass('jaxy'); 
                                  },
                                onComplete: function() {
                                  box.removeClass('jaxy');
                                  }
                                }).request();
                          }

                         else {
                               	this.send({
	                        update: box,
		                onComplete: function() {
			        box.removeClass('jaxy');
		                                   }
                                     })
                         }
	           })      
              })
         });


Mootools library. Easy enough to convert to prototype, these functions are very similar.

custom button_to helper goes in application helper. This allows rel and class name html
attributes to be set in the form tag generated by the button_to helper -- rel and class 
name tell the ajax function which http method to use (ie, 'delete') and what element to 
update with the response. 

      def button_to(name, fmeth, fclass, options = {}, html_options = {} ) 
        html_options = html_options.stringify_keys
        convert_boolean_attributes!(html_options, %w( disabled ))

        method_tag = ''
        if (method = html_options.delete('method')) && %w{put delete}.include?(method.to_s)
          method_tag = tag('input', :type => 'hidden', :name => '_method', :value => method.to_s)
        end

        form_method = method.to_s == 'get' ? 'get' : 'post'

        if confirm = html_options.delete("confirm")
          html_options["onclick"] = "return #{confirm_javascript_function(confirm)};"
        end

        url = options.is_a?(String) ? options : self.url_for(options)
        name ||= url

        html_options.merge!("type" => "submit", "value" => name)

        "
" + 
          method_tag + tag("input", html_options) + "
"
      end


usage:

<%= button_to 'Destroy', 'delete', 'myupdatetarget',  specialty_path(specialty), :method => :delete %>

where 'delete'  adds rel="delete" and 'myupdatetarget' adds class="myupdatetarget" to the form
tag. The Rails button_to defaults only allow you to add a class name to the form input field.