When I built our site we needed tabbed menus in some places - largely to stop the menu getting too deep. If you don't know what I mean then take a look at http://www.egyptological.com/participate/write-for-us
I was inexperienced and in a hurry, so I built it into the theme. (A child theme of Hybrid.) I am in the process of re-coding the theme and moving more of it into plugins to make it modular and easier for me to configure different sites as needed. The latest thing to move to a plugin is the tab menu. Now I can just keep it for personal use, or I can put in the extra work to make it more flexible and release it to the public. There is no point in doing that though if nobody would be interested.
I looked at a number of plugins and didn't like any of them. Menus were hard to maintain. My approach is simple. In your main menu give any item which is to be a tab parent ("Write for Us") on the example page, a CSS class of tab-parent and it and its children are displayed as a tab menu. No extra menus to maintain. Trivial to turn on and off. My main menu has about half a dozen of them, at different depths.
It's all working but if I am to release then I need to sort out the CSS which is still in the theme. At present that is being used to hide the unwanted part of the main menu so it doesn't display twice - that needs changing to edit the menu to remove the section rather than hide it with CSS so it works with JS menus too. I also would need to test with pure Hybrid and maybe some more themes.
At present it is inserting the tab menu at hybrid_before_content but I can add any extra hooks people want - I have a plugin options page set up already.
There are two constraints:
1) It only works with one menu. It might be possible to get around that but so few sites use two menus I honestly cannot be bothered to spend the time
2) The tabbed menu has to be lower down the page than the main menu - i.e. processed after the widget or theme area which contains the main menu. So if you have a menu in the footer, cannot help, sorry.