I work for a company that produces Mining Investigation reports for property in the South West of England and I have spent the last 12 months digitising abandoned mine plans, geological survey, old ordnance survey maps etc onto a custom built GIS in QGIS. However, many of archive and analogue maps are extremely difficult to fit using a georeferencing tool, be it ARC or QGIS.
Therefore, it would be a lifesaver and an invaluable tool to be able to import and overlay ungeoreferenced raster images into the QGIS Desktop and be able to manipulate them over layers already in the browser, almost like a lightbox.
Best Answer
There is a free web-based georeferencing tool designed for old inaccurate maps here:
http://warp.worldmap.harvard.edu/