After attempting to extract annotations from my Sony PRS-350 a long time ago, and finding only a very strange format, I decided to not pursue it further (especially as the Internet didn't have any clue about it neither).
Now that I have acquired a new ereader, the kobo aura, I thought I'd visit this topic again, but with my new toy.
My main reason to do this is that I often highlight words in ebooks for lookup.
It would be great to extract them so I can have them offline for later reference and practice.
For the Kobo Aura this proves to be a breeze.
Thus I made a bash script that will do all of this at once for all books for which there are annotations, and output a HTML table containing the definitions.
Download it from: translate_kobo_annots.sh (6 KiB, modified on 30 December 2015, MD5 86534491a86304faa566ce573a5b6da5) and run
translate_kobo_annots.sh html -d ./dict/ (with your Kobo connected) to create an HTML file.
The read more link shows some more details, and contains a listing of the file.