gistfile1.rbx

Merb::Router.prepare do |r|
  
  r.domain("admin-domain.com", :controller_prefix => :admin) do |admin|
    admin.resources :users
  end
  
  r.domain("content.com", :controller_prefix => :site) do |site|
    site.resources :users
  end
  
end

# when on admin-domain.com and url(:admin_users) => /users
# when on content.com and url(:admin_users) => http://admin-domain.com/users

# ----

Merb::Router.prepare do |r|
  r.domain(":account.saas.com") do |saas|
    # Here there is no controller namespace
    saas.resources :users # This has the :account set
  end
end

# when on foo.saas.com and url(:users, :account => "foo") => /users
# when on bar.saas.com and url(:users, :account => "foo")  => http://foo.saas.com/users