I've been working on a problem that this browser extension would solve really well. I've got a photo gallery with a hundred thousand photos in it where I implemented near-infinite scroll by creating a really tall div and then drawing about 2x as many thumbnails as are needed to fit in the current viewport, which is updated when the user scrolls. They are square thumbnails so it is easy to calculate exactly where to position each of them.
The advantage of this over infinite scroll is that the scrollbar is always there and always accurate, so coming back to the page after following a link works properly. Also, I don't have to send the information about all 100k photos on page load (I can load it with AJAX).
Cool, but seems like with your implementation, you can scroll too fast and get lost in the "white". Not sure how fix it, possible showing somekind of grid before loading the images could help.
Thanks for the feedback. Rendering a grid would be easy to do and would help a lot.
I am debouncing the scroll events right now and haven't tried making the timing more aggressive so that it doesn't sit at white for as long as it does. Right now the long pause is just because of a timer.
The advantage of this over infinite scroll is that the scrollbar is always there and always accurate, so coming back to the page after following a link works properly. Also, I don't have to send the information about all 100k photos on page load (I can load it with AJAX).
A demo of how it works is at http://beta.hypercheese.com/search, and the code is at http://github.com/jewel/hypercheese/.
It sounds like having this in the browser will allow for much more complex layouts.