Of interest for quoting_mungo, who made the suggestion, and other people with multiple projects who'd like to organise their character profiles on the site: If you have added character lists (the first option on the "Manage References" page), which don't require links anymore, you can attach individual characters to them. That's done on the "edit" page of the character in question.
The list of your References will then be sorted under those lists. You can see the effect on my page.
Oh, and you can upload icons of the characters, to spiff up the list a bit.