Opera is planning to add voice input and output to it’s next browser-version, according to this article. That would mean that your browser asks you where you want to go today, or ask you for the input of a form, which you can then give just by saying it.
Opera also has nice features for holding presentations, combined with speechtechnology, you could simply ask your browser to go to the next slide, instead of walking to your notebook and pressing a button.
This will also make good site-design even more important.
Can’t wait to test it!