When you are logged in, you are now able to mark items in the current auction as favorites by clicking the "Mark Favorite" button that appears below each item. Once you've marked an item like this, the favorite count on the left side will increase, and the button will change to "Clear Favorite". Pressing that will reduce the count and return the button to its original "Mark Favorite". When one or more items have been marked, you can click on the category count to list all your favorites together.
Favorites are only available for the current auction. Also, if you sign in as volunteer or admin without picking a valid member (So that it says in the upper corner "Logged in as Admin" or "Logged in as Volunteer".)
How it works - if you visit a member profile page (which is now bookmarkable, meaning you can email a link to it and the recipient can click into that page after they sign in) you will see a line at the top of the comments that says something like "Favorites 1234,5678,9012". This is a list of internal item numbers of the items marked as favorites. Leveraging this existing comments area as a place to store favorites made it easier to implement this feature because it avoided the database structure change that would otherwise have been required.
There's a "Clear Favorites..." admin feature which clears all member favorites and some email related info from member notes where they are stored. Use this between auctions, so that favorites don't fill up the notes space - If you never use this feature, members who add a lot of favorites could eventually be unable to add more since only current year items can be added/cleared by members.