There is an Engineer I work with who is into photography, and has been intermittantly shooting an 8x10 for the past 10 years or so. A few weeks ago he brings in a print to hang on the wall. A 4x6. That is 4ft x 6ft. Razor sharp edge to edge, and you have to look really close to see the grain.
For about the last two years he has been building a horizontal enlarger for his 8x10 negatives. He designed the entire thing from scratch. The light box is illuminated with green & blue LEDs which are controllable for use with multicontrast paper (custom control circuitry with feedback for stability, and tons of light available for reasonable exposure times). He tinkered with & tested many ideas over the last couple of years, and has ended up with a great system for making BIG prints. The last few months we often discussed methods for handling large pieces of wet paper, which was his last obstacle to overcome.
Quite an accomplishment. If I can ever get over there & if he will let me shoot some picts, I will post them.