In ASP.NET MVC there's basic convention based route maps by adding MapRoute calls to the RouteTable. This is counter intuitive and provides little features.
With http://attributerouting.net/ you can stop thinking about routes as something configured in Global.asax, instead use it where it belongs, on your controllers and action methods.
It also provides some more features (that Html.ActionLink etc benefits from) such as "AppendTrailingSlashToUrls" and "UseLowercaseRoutes", amongst others.
Do check it out! It's really good!! It's great!!!