I came across a site called Imagekind which allows artists, designers and illustrators to sell prints of their designs online with no initial outlay. I know cafepress and similar sites offer the ability to customise a lot of different items but this site seems to specialise in prints and offers buyers the opportunity to have the prints framed for which the artist also receives a commission.
Designers can have a free account which allows them to upload a maximum of 24 images (you can pay to upload more). You then choose how much you want to mark up your print price (your commission). You then market your site – perhaps with a link from your design blog, images can also be found through a search on Imagekind itself.
I haven’t tried the service but would love to hear from anyone that has.