This week-end, I remembered my Psion where I kept memos attached to to-do entries. It was a useful feature popular amongst many psionists.
Now - although this may not have been intended - it is actually reasonably easy to recreate in Rainlendar using the wiki-links:
Provided there is indeed such a file (julegaver2007.txt in the cal directory), this works like a charm. Click on Julegaver, you get the entry, click on the text in the last brackets (julegaver2007.txt, or whatever), you get the file.
However - I would have preferred if I could use relative links to the file-system (skipping the path), but if I do, Rainlendar/OS goes off in search of a URL instead. The advantage of using a relative link, would be that the feature would work under Linux as well.