I remember there was a similar add-on for firefox. It stored the entire content of pages you visited on your local hard drive and you could search through it. It's called breadcrumbs. How is boomtango different from breadcrumbs???
I haven't installed it, but from looking at the docs, I think there are couple major differences.
One is that we provide a UI with several views that let's you slice and dice your way into finding the content you are looking for. For instance, you can view your history visually in thumbnail view, by a variety of calendar views, or by the category of your content.
Second, we look at the content (and possibly your actions) to determine what the content of the page is and what you've done, and put it into categories. All the videos you've seen or searches you've done, etc, will be categorized so you can quickly find by the type of content for which you are looking.
Third, we include an open greasemonkey style api so that this can be extended (the only one we have right now is a "Hacker News" plugin that records every article you click on from hacker news). For instance, we plan on adding plugins that don't fit for the general public. Conceivably, you could add a blogging plugin that might record all the comments you add to a blog, or a developer plugin that records all the api calls you look up on various sites whitelisted sites so that you can quickly get back to that content.
uggh. That's a bug. We'll fix it in the next update. We don't change the default throbber; not sure what might be going on with that but I'll take a look.