Open an .ico file in Photoshop or Illustrator?

I have some icons I'd like to purchase and use from iconfinder.com, but they are only available as .ico files. I want to use these as part of a user-interface on a website, so I need them as either bitmap or vector format that I can bring into Photoshop to produce transparent .png files.

Does anyone have any suggestions on how to get .ico files into Photoshop through some third-party application? If it matters, I am using a Windows computer.