ArchiveTeam has saved cached Reader feed data for 37.3M feeds so far, and even though this seems like a lot, it still doesn't include many of the feeds people are subscribed to. Hence the request for OPMLs/subscriptions.xml files.
If you're interested in being able to read old posts in some future feed reading software, or just like having the data preserved, you can upload your OPMLs and ArchiveTeam will make its best effort to grab the feeds.
Also, if anyone has billions of URLs that I can query, I could use them to infer feed URLs and save an incredible amount of stuff. See email in profile if you do.
If you're interested in being able to read old posts in some future feed reading software, or just like having the data preserved, you can upload your OPMLs and ArchiveTeam will make its best effort to grab the feeds.
More details: http://archiveteam.org/index.php?title=Google_Reader
7TB+ of compressed feed text: http://archive.org/details/archiveteam_greader
Also, if anyone has billions of URLs that I can query, I could use them to infer feed URLs and save an incredible amount of stuff. See email in profile if you do.