Based on revenue and catch-all use ALONE I'd put the value at low middish $xx,xxx USD.
HOWEVER, because it's only a sub-domain of .us.com, that drops the value of it, in my view, sharply to $xxxx (ie. ~ $5000 USD).
Much of the value of pure type-in domains is in development and future resale - but due to the uncertainty of .us.com domains, the bulk of the value is wiped out... CentralNics terms basically guarantee nothing; as most here already know, they are not ICANN accredited and .us.com isn't a recognized TLD.
http://www.centralnic.com/terms
In short, the domain is worth way more than $0, but not 6-figures ... more like around 4-figures, but this is only my opinion ... and if multiple motivated buyers get interested in the domain, the price could easily get into the 5-figure+ range.
Ron