Amazon Kindle

hmm so I'm trying to keep track of what I've read and what I haven't.

Amazon's "You've purchased this on xxx" is useful BUT

Doesn't take into account:

• different formats (kindle/paper/hard)
  
• different amazon.com/uk/de purchases (without login in seperately)
  
• non-amazon purchases
  -- physical books
  -- stored in Calibre
  
  

How do people track all of this ? I have ~400 books in Calibre, probably about 200 in Amazon UK, 100 odd in Amazon US and about 600 physical books.

Ideally I'm looking for something site / something to keep it all in sync.

I'm so primitive I note when I start and finish books in a separate Google calendar.

It's manual, but it makes it so simple to answer questions like "What did I read last summer?" or "When did I read x?". And in theory I could use the API to go through and find things started "Start: title by author" where there is no "Finished: title".

I have a lot of Google calendars, I use calendars for things that people don't think about... I have others that store logs of every phone call I've ever made, or films seen at the cinema. It's basically my version of a diary, but filterable, searchable.