I love firefox extensions and use a bunch of them. The plugin architecture has made the browser much more powerful. There are many things that you can do with a browser plugin, but the two most obvious things are add functionality to the browser or add functionality to the page.

A good example of the first is the delicious firefox extension. I use the delicious extension, largely to post to delicious, but it can also be used to navigate your bookmarks in the browser via a sidebar that looks like this:

I have to say that I am not a huge fan of plugins that change the browser's user interface. I am a fan of simplicity when it comes to a browser.

The second approach is to deliver the functionality on the page. This week I saw Mahalo make a big change to their extension called Mahalo Follow. I've had Mahalo Follow installed for a while now and in the past, when you did a Google search, it opened up a sidebar (like the delicious sidebar shown above) with additional search results from Mahalo. It was occasionally useful but not always and I found the sidebar annoying, particularly the need to close it.

Yesterday, I did a search on my name on Google and instead of opening a sidebar, this came up in the browser.

I was startled so see real value being delivered in a simple elegant and quick way. I sent an email to Jason Calacanis, founder and CEO of Mahalo, asking how long they've been doing this. He said for about a week and naturally suggested I blog about it. And so I have.

I am curious if others agree with me that delivering the functionality on the page instead of in the browser is better. I certainly think it is.

Full disclosure: I am a small investor personally in Mahalo and our firm was an investor in delicious before it was sold to Yahoo!