There are literally hundreds of utilities out there designed to download videos from the Net, mainly aimed at YouTube.
By it's name alone, DownUtube doesn't pretend to do anything else (although it does work with a few other sites too) but at least it does the job well. DownUtube allows you to download embedded videos and multimedia from Google Video, YouTube, Apple.com Movie Trailers and IMDB.
Like most good video downloaders, DownUtube features an integrated search facility to help you find videos on the various sites which means you don't even have to open a browser. It can also follow RSS feeds for your favourite users on YouTube. If you can't wait for your clip to download, then you can also play them because they download thanks to an integrated player called MPlayer. There are various bugs that need ironing out however - sometimes downloads will stop for no apprent reason even if your connection is fine and some videos can cause DownUtube to simply crash.
As a simple solution to your video downloading needs, DownUtube is a great search utility and downloader that eliminates the need for a browser.