Recently Bethesda Softworks released the Fighter's Stronghold of Battlehorn Castle. After a simple skirmish with a couple marauders you gain the deed to the castle after having defended it. Now it's time to do what you do best in the little house expansions. Gold spending time. So after upgrading your castle significantly, you think you are finished. However, you are not!
In addition to owning a sweet new castle, you get a couple new features. You get a vintner to create special wines that buff you on the battlefield. You can hire a taxidermist to place life-like protrayals of the enemies you face within your castle. You can hire a trained swordsman to duel you and help you increase your battle skills. There are a couple hidden passages. There is one leading from the basement to a false wall in the guard's quarters, then another in your private quarters leading to a table on the roof. Apparently there is a secret treasure vault, but I have not found this yet~
Nice little free add-on for those that own Elder Scrolls: Oblivion for either PC or Xbox 360. I recommend downloading it!