Old maps show this building near Sherman and Greenwood in Evanston used to be a wooden toy factory in 1920. Upon further research, this turns out to be the original Tinkertoy factory–whoa! Evanston would be the home to at least one other Tinkertoy factory, employing about 100, but by 1973 the company was bought out and manufacturing was moved elsewhere. Now the building is used by Leapfrog Online, a marketing data company.
Sanborn Fire Insurance Map, 1920: