CHECKY 0.5.1 for Mozilla and Netscape

The Checky plug-in is a simple Interface for web content and resource developers to free and commercial online Validator and Checker services.

With Checky you can now easily set-up, combine and use 18 different online Validator and Checker services. Simply choose your services with Checky-Agent, then browse to web resource and press F10 to display the results of the selected services in a new browser tab or window.

More information can be found here.