Many feeds are limited to the last X posts. (How) does this workaround that? Are there some big feed archives or caches on the web?

This is a fantastic idea, I often come across an old blog that I want to read through chronologically.

Edit: Something like this build into Google Reader would be great.

There's a specific version of this for webcomics called Archive Binge.

http://www.archivebinge.net/

I don't know if this is all that interesting to hackers, but I've found it entertaining.

Great idea. Is it possible that it's better suited as a feature of an RSS reader?

Does not appear to support https feeds. Eg, mine:

https://secure.grepular.com/rss

tad sad I did't know about this years ago, thinking of all the things I wish could have lasted longer. oh well.

Too bad that most RSS feeds only contain the last ten items, not the whole archive.