I need to share those types of resources across several ASP.NET web sites. The approach I tend to is to create separate web application for common master pages and separate web site for common CSS, images, etc. The problem here is that I will no more be able to reference common resources using tilde, instead I would have to use URL of common web site with those resources.
There is also an approach delegating source control to manage this which I don't like because you would have to check in changes and update other web sites for changes to take effect.
Are there any better ways of sharing those resources across ASP.NET web sites?