YUIAspNet controls for ASP.NET Ajax

AutoComplete Usage info Client Side Local data Remote data Custom format Button Usage info Skinning Regular button Link button Split button Menu button Checkbox button Radio button Calendar button ColorPicker button DropDownList button Slider button TreeView button Multi select button Calendar Usage info Localization Multiple selection Client side Pop-up calendar Charts Usage info Chart Skinning Remote data Custom tooltip Line Chart PieChart Column Chart StackedColumn Chart BarChart StackedBar Chart ColorPicker Usage info Minimal UI DataTable General usage info Lazy loading Fixed header Paging Row formatter Cell formatter Column Drag & Drop Existing GridView Dialog Usage info Using IFrame Custom form Editor General usage info LayoutManager Usage info Outlook layout Nesting LayoutManager Logger Usage info Menu Usage info Horizontal menu Vertical menu Dynamic menu Context menu Animation Paginator Usage info SimpleDialog Usage info Client side Loading dialog Slider Usage info TabView Usage info Client script usage Tab orientation Tooltip Usage info Client side Skinning Tooltip re-use TreeView Usage info Lazy TreeView Autopostback TreeView TreeView Folder Skin TreeView Arrow Skin

Animation support Here's an example usage of YUIAsp.Net Menu control.