Is there any downloadable application/plug-in which one can download for Firefox, which fools web-sites into thinking that you are viewing their pages with IE (or any other browser, for that matter)?

I remember being able to do this with some other browser, I think it was one of the later versions of Mozilla (1.x).

User Agent Switcher will do that. I notice there is a negative comment about this extension on the Mozilla extensions site. You may prefer to go here instead. Extensions at this site tend to be updated more quickly.

You'll have to give FF permission to download from the site (gives a warning bar at the top of the browser). I have installed all extensions for FF from there for some time now with no problems resulting.

The extension can be left operational all the time, although perhaps that isn't a good thing to do. Site writers won't be inclined to do anything about their IE only sites if other browsers always identify as IE. I generally e-mail webmasters these days and say the site won't work properly in my preferred browser. I've had some positive answers too.

Answers such as, 'Why don't you take your browser and...!

Well. not really Most say they will do something about it in future updates.

Opera has the option to identify as IE as well.

Brilliant! Thanks a lot, TW.

I agree about trying to get site-writers to make their pages viewable in browsers other than IE, hopefully people will soon begin to learn about the very existence of alternatives to it. The wide-spread media coverage surrounding the release of Firefox 1.0 has helped quite a bit, I would assume, in this regard.

Edit: Not that I plan to use this extension for all my browsing purposes, it's only for some of those pesky sites which just refuse to allow browsers other than IE to access them.

Have you come across those pages where FF displays only a load of source code but they work properly in IE? They are a bit annoying. The switcher extension has no effect on them. This is where 'IEview' comes into its own. Although it shouldn't really be necessary to use it in order to view a web page.

I don't recall having visited any such page in the past, but if I do, I could easily enough use IE to view the page; I don't want to have too many extensions downloaded.

Found an example of it referred to in the Firefox forum.

Link to FF thread

Ah, I see; so then it's primarily the fault of the server on which the web-page is stored, and not that of the browser.