I think back to 2005, and wonder how cool it would be if I had a folder fully of web page snapshots showing not only what I was interested in back then, but also what the web looked like then. Even though many of the blogs I read back then are likely long gone, if I had an archive that showed the pages the same way they existed, I could still browse through the same stuff today that I thought was useful or interesting back then.
That's what SingleFile does. Under the hood, it uses data URIs to capture page assets and encode them into the text of the page itself, so the resulting file, while as large as the sum of the assets it contains, is a stand-alone artifact that can be opened in any browser without an plugin at all. In my testing so far, it works extremely well.
There's an automatic archive function I haven't played with. I wonder the feasibility of indexing the archive files and layer search on top of the archive? Those two features together would be quite potent.