Does anyone know the history of attempts to build a union of the unemployed
> in the US or attempts by organized labor to reach out to the unemployed?
>
I know a small amount about the Communist-led Unemployed Councils of the 1930s. Since their main on-the-ground campaign was the organizing of mass resistance to evictions and foreclosures, some of the later Communist tenant organizers in New York styled their activities after them. One can find a fair amount of relevant information by Googling "Unemployed Councils"; Labor's Untold Story also includes a decent section on them.
-- "Hige sceal þe heardra, heorte þe cenre, mod sceal þe mare, þe ure mægen lytlað."