Displaying ActiveRecord results cached in memcached in random order

I am using memcached to cache a query that returns a set of ads which are then loaded into a div where I'm using jQuery and the jQuery plugin ScrollTo to cycle through the ads.

I want populate the div that contains the ads in random order each time the page is loaded so the same ad isn't shown first, and when the app cycles through the ads that the ads appear in different order.

Wha开发者_开发知识库t's the best way to take the result set from the memcached store and arrange it randomly for display?