Jake Miller lays out 7 fantastic ways to make the most of your Chrome bookmarks bar, and it’s quite a list. None of the hints are specific to Chrome, and will work in any browser. I would add an 8th to the list:
8. Bookmark Gmail searches
Any search you perform in Gmail is bookmarkable (if that isn’t a word, it is now). Do you want to only see the unread messages in your inbox? Use in:inbox is:unread as your Gmail search, and then bookmark it. Do you only want to see the last days worth of new messages that you haven’t read? Try in:inbox is:unread newer_than:1d. For more ways to search Gmail, check out this article and more information here.