Is There Any Javascript (and Client-side) Wget Implementation?

In order to provide a service for webmasters, I need to download the public part of their site. I'm currently doing it using wget on my server, but it introduce a lot of load, and

Solution 1:

Does an implementation of wget exists in Javascript?

I doubt it due to the same origin policy restriction built-in browsers which prevents you from fetching contents located on other domains. If the contents is located on your domain and you are not violating the security policy you could use AJAX.