I've dabbled with pinholes for a few years, not really spending enough time on completed exposures to actually present it in any way. Most get scanned and posted on the web in 'see what I did' mode
My biggest pinhole camera is an 10x7.9 (long story!) made from matt board. My most structural device is a 5x7 one made from masonite which zooms thru about 150 to 240mm. I recently bought a 4x5 neg holder to build into a 'Lenardo' style camera.
Unfortunately I missed World Pinhole Day this year, but if you haven't seen the site, have a look (www.pinholeday.org), lots of piccies to browse.