TrafficZ is one of the first domain parking services. Monetization has suffered under Bing. For a time I kept many of my lower-traffic domains there because they have really great stats. They also allow you to include whatever simple html content you want on your landing pages, such as links to your other sites (but no javascript or similar code). You can change keywords for your site on the fly and see the results immediately. TrafficZ would like you to have at least 50 domains, but exceptions are made - So ask.

The newer landing pages look more like real sites than most landing pages. With their 5.0 service the site has a new look You do not have to choose between pay-per-click and pay-per-impression. Their MaxPay program will pay you both ways. This makes them especially good for domains that get a lot of pageviews but few clicks.

You can create a custom banner for your site. This allows better "branding" with the same look and feel throughout your domains. Customer service is excellent. TrafficZ allows you to make changes in real time to the keywords on your sites, no waiting for someone else to approve the changes. Adult sites recently got sexy thumbnail images desigined to increase click-through.

An example of a trafficz domain is webmortgage.net