Hyascent's hourglass diffusers (you turn it once or twice a day, the scent drips from the top to the bottom and is diffused through the wood rings) are pretty darned good-looking, with a price to match ($169 at Neiman Marcus — only $11 less than the Diptyque version*). They last for about 6 months, and they say they are going to sell refills but there aren't any on their website yet. There are 9 scents, not one of which grabs me offhand but Bourbon Joy (vanilla, mandarin, cedar and muguet) or Bliss Me (fig, jasmine, violet leaf, vanilla and amberwood) might work for fall.

* Diptyque's Le Sablier comes with 75 ml of juice; the Hyascent comes with 180. No idea if they are of equal strength, though, so that might be misleading in terms of cost.

WANT. WANT. WANT. (But would not pay as much as they're asking for it, as usual.) A Pencil Shavings Diffuser from Anya Hindmarch. Looks like pencils, smells like pencils. "The new pencil pot diffusers are made using an innovative technique that uses ceramic ‘reeds’ to diffuse scented oil into the room. A modern take on the classic reed-diffuser, 'Pencil Shavings' releases a dry woody scent infused with notes of; Mandarin, Pink Pepper, Cedarwood, Rose, Cypress, Novelty Erasers and Fresh Notebooks." £99. Also available in Lollipop and Chewing Gum.