Sliding menu for parent and subcategory

Hi!

I’ve been trying to find a plugin of somekind that can help me save some space in my menu containing my categories.

I use parent and subcategories, and I have alot of them, so I want somekind of a sliding menu that shows the parent category, and when clicking or with mouseover the subcategories will show.

Hven’t been able to find anything that works, probably I’m not sure of what to search for.

Does anyone have any ideas of plugins or solutions that might help me?