i think telerik has some properties like drag and drop:
http://demos.telerik.com/aspnet-ajax/grid/examples/programming/draganddrop/defaultcs.aspxthe problem is that it isn't free, but you could try to build a similar grid like this:
http://www.codeproject.com/KB/webforms/DragAndDropGridView.aspx(i tried it in firefox and it works)
hope it helps