From my HN link:

> 1. Why does neverssl.com use Javascript to redirect to a random subdomain?

> Over the last year users reported that some networks aggressively cache the fake DNS and pages they use for wifi capture. Neverssl.com now works around this generating a request to a random subdomain - this will bust any DNS cache, and any HTTP cache. It also means that if your browser or ISP caches the Neverssl.com page itself, that's fine.