marking up the web

The article Five Ways to Mark Up the Web explains 5 services to mark up content on other web pages. A few look like they can be read without plugins or downloads (which is important for readers; I can do a plugin to create content, but I want everyone to read them):

- Diigo - searching my own bookmarks is great; search fails on group content...?

- Fleck - I cannot find any public search utility

- TrailFire - I couldn't download in my Linux FireFox ('cause tried to save the PHP files); plus it gave blank pages when I tried to look at some of the existing content