Often I have posted here about the building plans held by Richmond upon Thames, how the Local Studies Volunteer Support Group have accessioned and catalogued the plans; more recently assisted in producing a booklet for an exhibition. Today that exhibition was formally opened at Orleans House Gallery, there is a smaller collection of plans in Richmond Museum. The plans are mind blowing, beautiful works of art in themselves, you can see them online, to see the framed plans themselves is awesome.
http://www.calmview.eu/Richmond/calmview/ is the catalogue for Local Studies.
Found this example, think this was built, many plans were not approved of course.
This is the original press release from the Heritage Lottery Fund way back in March 2010.
An oriental-style café, complete with onion domes, could have been a prominent landmark in central Richmond, and Twickenham might have gained its own theatre in the early 1900s if plans had come to fruition.