Squidoo lens - is a poiwerful community where you post a smattering of information about one topic. It is a collection of all different elements to bring "focus" to the topic like a lens...
Blogger Blog - Owned by Google this simple blogging platform is an easy way for you to post information and allow comments. You are flexible to host it with Google or on your own domain.
Wordpress Blog - More powerful than Blogger in software applications and add-on tools, you can highly customize wordpress and ideally run it on your own domain with lots of SEO plugins and other integrations...
Use them all for more presence...