Trailfire lets you leave "marks" for other visitors to read on web pages that you visit. You can join a series of marks together into a trail and share them via sending email or publishing it on the Trailfire site. You can also add a link to a trail on your web page or blog or even to a particular "mark" on the trail.

Creating a trail is easy. Sign up at Trailfire. Download the extension for Firefox or the IE7 add-on Watch the screencast that shows you how to drag the sticky note bubble from the toolbar to the page where you'd like to leave a mark.

Trails may be private or public.

Thanks to Darlene and Lee at LGR Blog for pointing out Trailfire.