It's a web app someone made, I think linking to interesting web apps is almost always on topic as long as they are more complicated than a single serving web site.
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looking forward to when pg lets us starting tagging things as meta
So if I made a webapp "Cats On Keyboards", which displays pictures of wonderfully cute kitties blissfully sleeping on keyboards, then that would be HN material?
I am very, very interested in hearing a discussion of the business, marketing, or technical aspects of ICHCB on Hacker News. That goes ditto for just about any site, from a titan of Internet publishing down to what some high school kid whipped up in his bedroom which has a total of 100 users (as long as there is some hook to it).
However, linking to the front page of a site just because it is on the Internet probably wouldn't pass muster with me.
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looking forward to when pg lets us starting tagging things as meta