The Opera Hotlist is where the different panels are. Internal panels include Bookmarks, Mail (M2), Contacts, History, Transfers, Links, Windows, Chat, Search, and Notes.
The real power of Opera is that any bookmarked webpage can be turned into a panel, and added there for easy access. Especially pages formatted for smallscreen devices are perfect for this—try it with any page at this WIKI!
Just add /sidebar to the end of the URL. So to turn this page in a panel, create a bookmark out of this URL.