How about kiddie amusement rides as temporary installations in traffic circle "parks"

Most of DC's "traffic circle" park spaces are run by the National Park Service, so this could never happen, but the Austin American-Statesman has an article, "Austin’s loss can be your gain; want to buy a kiddie train?," about the demise of a small children's amusement park called Kiddie Acres, with the rides going up for auction.

Wouldn't it be cool to acquire the airplane and boat rides, and the Merry-Go-Round and truck them around the city as temporary installations in parks, commercial districts, and other open spaces, just as splash fountains are an increasingly desirable park and business district amenity?

Note that this line of thinking was triggered by one of the blog's e-correspondents, who suggested putting a kiddie train in as an attraction as part of the National Mall, mentioning that the Mall had more of these kinds of attractions at one time.

Interestingly, around that time I bought a vintage postcard for a regionally-located similar kind of amusement park and attraction, the "Blue Mountain Railway" at the Braddock Heights Amusement Park in Frederick County, Maryland.

Many cities have "piers"--Santa Monica, Chicago, Copenhagen--with various attractions including Ferris Wheels, as does the area's "National Harbor," located in Prince George's County ("National Harbor Is a Private Urban Island Designed for Fun—If You Can Get There," Washington City Paper).

Alternatively, the massive parking lots at RFK Stadium lend themselves to such a treatment.