So, one of the open themes currently at JPG Magazine is Rasterbator. You can use this online tool (or download it -- Windows only, I believe) to create huge posters of your images (photos, drawings, etcetera) output in raster dots, like for offset printing. It creates a PDF with all the pages so you can then print it out and tile them. Very nifty!
That's Day 33 and Day 34.
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