Ken-Doll -- now you've got me looking at all the policies!
(And as a plug for MoMA, it's significantly closer to Hermes Madison than the Met is. )
Met Museum: "All backpacks,
large bags, and large umbrellas must be checked in at the coat-check facilities."
AMNH: "Items
not accepted in the coat check include perishables, wallets,
purses, musical instruments, bikes, computers and
other items deemed to be of high value." [Nice exception there]
Brooklyn Museum: "All packages,
large bags, and umbrellas must be checked."
Dia Beacon: "Visitors are required to check all backpacks, packages & open parcels, umbrellas, and
bags/purses larger than 11X14 inches."
Guggenheim: "All backpacks, large toddler carriers, double-sided strollers, jogging strollers, large umbrellas, and
bags or packages larger than 16 x 16 inches (40 x 40 cm) must be checked."
Neue Galerie: No limitation.
New Museum: "The Museum requires visitors to check backpacks of any size, shopping bags, and
all bags larger than 11 by 17 by 6 inches (28 by 43 by 15 centimeters)."
Info not available online: Whitney, ICP, Onassis Cultural Center, PS1
Xiaoxiao -- Maybe! Usually go on a whim 2-3x/wk.