The Best Firefox Extensions
Browsing & Downloading
This is an ABSOLUTE lifesaver. In websites where the content or articles comes on multiple pages, AutoPager preloads the pages, so you don't have to continually change page and refresh the content all the damn time. It's a little hard to explain, but download and install it, and I promise you it'll bethe most useful extension you have.
Allows you to download .flv videos from Youtube and similar websites.
Notifies you if your Gmail accounts have new email. Works also if you don't have an @gmail.com or @googlemail.com address (i.e. if your websites emails are hosted with gmail). Also works for multiple accounts. Lifesaver.
Allows you to use your GMail account as extra online storage.
A very useful tool for those who are building websites or making images in Photoshop, etc. It includes a color picker, to see what color any section of an image is. It's really useful for finding out exactly what color to make that ←div→ rag under the header image, etc.
A great tool for anyone building websites. Allows you to change CSS properties on the fly to see how something would look with certain color or width properties, without the bother of having to upload a new CSS file each time.
An entire FTP program, located inside your browser. It's not fantastic, but it is a 1MB extension, rather than a massive 50MB standalone program. I never btoher installing an FTP client at all on my machines now.
A nice extension so that you can see how pages will look in IE without having to load up the separate program - just saves time. In reality, I just launch IE for when I need to view windowsupdate.com, so I'd recommend only installing this if you build a lot of websites.
P.O.W. - Plain Old Webserver
Allows you to run a webserver from your browser. As with FireFTP, it has a lot of shortcomings, but if you don't need the mass of features that come with Apache or IIS, then give this a go before you install them and clutter up your PC.
Web Developer Toolbar
Brilliant tool for web developers, and even for those who arent. Allows you to fill in forms, change the size of the firefox window, and millions other useful tools.
An extension to Firebug (yes, an extension to an extension) that allows you to check the loading speed of a website.
BugMeNot is a website that lists common usernames and passwords for websites that force you to register to view content. This can be really annoying for forums, etc. So, use this extension, along with bugmenot.com's usernames and passwords, to speed up the process.
Turns links in the text of the page to clickable links. So if http://example.com appears in the text of the page, it turns it into a link. Visit this page after installing it to see what I mean.
Just install it and visit google images. It shows you them all in a brilliant scrolling list.
Reloads pages at pre-determined time intervals. Great to leave a page displayed, reloading every minute, so that you can check it from across from the room for an update, etc.