The Dyson website recently launched a refurbished section, where you can buy its cleaners with around 30% off standard prices. Since its website is one of the cheapest places to buy its products anyway, this is a decent deal if you want one.
Most items listed as refurbished will have been returned unused, so should reach you looking brand new. Where the products have been used before being returned, parts will be replaced to restore them to nearly new condition.
All refurbished products are tested before they're sent out, and in this case they come with Dyson's standard 2-year guarantee (1-year on handhelds), so you don't lose out on that front either.