Windows 7: Alternatives to Prism, WebRunner, Bubbles?

I've googled for and checked "Alternatives To" but cannot find a currently maintained application that duplicates the functionality of Mozilla Prism, Web Runner, or Bubbles. Each of these applications allows you to make a web page into a separate, mini-desktop application. They tend to look as if they're custom Adobe Air widgets. Is anyone aware of a product with similar functionality.