A custom container view controller for iOS 5.
TPScrollBarController with a similar layout to UITabBarController, except the "tab bar" scrolls (yay!).
It also consists of fully customisable UIButtons (rather than UITabBarItems) and dispenses with the 1:1 mapping between bar buttons and controllers.
Lack of UI chrome is intentional.
Take a look at the "ScrollBarExample" project for a worked example or open build and run in Xcode 4.2 to see it in action.
Fairly basic, but it suits my needs. Maybe it will yours too :)