I dunno man, I kind of like being to re-start aborted transfers, too. I wish the W3C would tack that onto HTTP.
What do you think the range header does ( http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.35.2 )
Wikipedia's software is close in some respects -- you can include pages (but not, AFAIIA, selected bits of pages) in other pages. There aren't links in the UI, but it would be trivial to add them.
Actually there is an extension to do this called labelled section transclude that is in use in some wikimedia projects (Wikisource I think). Not to mention various hacks with <includeonly> or {{#ifeq:{{PAGENAME}}|some target.. Also backlinks (included which pages transclude the current page) can be viewed at the special page special:whatlinkshere. For example [1] lists all pages that are including the main page.
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