Bookmark to save your page on the book you're writing in so that it opens up to the page that is bookmarked. Secondly it could be really helpful to paste in the date from your computer, maybe with ways to change the format (i usually write my dates as "month.day.year" but someone may write "month/day/year" or "day/month/year" etc.). Both would be really nice for journalling and note keeping!
Bookmark could be a simple bookmark icon, and the date paste feature could be a clock :}