An idea for a post or series of posts I'd love for someone to write: the history of social change and what lessons the progress movement can learn from it.
You could start with Mark Lutter's list of social movements, which includes everything from environmentalism, to the abolition of slavery, to the Fabian and Mont Pelerin societies, to YIMBYism, to the Meiji restoration. Each of those would make a great post!
I'd be more than happy to see the posts here; it would also make a good blog in its own right.
This is an excellent subject area with a ton of material -- especially because so many 19th and 20th century social movements were so deeply tied with notions of social, economic, and technological progress, and often sought to use novel technologies to drive revolutionary change. In many cases, solidarity and freedom from hardship were seen as going hand-in-hand with modernity and industrialization.