Ads are a necessary evil in the world of websites. Thanks to ads, websites can easily be provided for free. Sites can even offer free hosting and download mirrors thanks to the revenue generated from ads.

Take a look at Neowin. This is a site that was designed with ads in mind. They fit seamlessly into the layout and blend in enough to be ignored. Yet, at the same time, they stick out just enough to be noticeable. Neowin is a very good example of a site with properly placed ads. All ProBoards forums also have great ad placement.

However, some sites go the extra couple hundred miles. The owners become money hungry and overload their sites with ads. Even so, regular banner or box ads are still not that intrusive. It's the ads that go out of their way to grab one's attention that really get on my nerves.

We all remember pop-up ads, right? View a site and an ad pops up in a new window while auto-focusing itself. That's just stupid. In fact, it's so stupid that a pop-up blocker is standard in just about every modern web browser. This ad would force a user to pay attention to whatever it was advertising whether (s)he wanted to or not. I don't know about everybody else, but I don't like being forced to focus on anything. If I visit a website, I have a reason to do so, and that reason is NOT to mindlessly look at ads.

As of now, pop-up ads may as well be a thing of the past. However, in their wake, some new intrusive ads have been introduced. So, in the world of modern advertising, I'd like to ask the question: "Which is the dumbest type of intrusive ad?" Here are the options:

1 - Pop-Under Ads
The direct follower of pop-up ads. They work in a similar way except that they don't focus themselves. Generally, a user will see a window pop-up and then vanish. Of course, that window just hid itself underneath the current one.

As far as intrusiveness goes, this one is probably the sneakiest. It's very easy to forget that these windows are open. A site can also easily open multiple pop-under ads in one go. I remember that I once went on a minor downloading spree on mediafire and easily had seven browser windows open by the end. I only work in one window with tabs. Annoying? Very.

2 - Flash Ads that can Extend Outside the Ad Area
I don't think Macromedia ever saw this happening when they first made Flash. Basically, the ad can alter its size and appear on top of everything else on the page. Here's an example:
u.roddyinnovations.com/users/Scorpian8867/extendedad.jpg

Notice how a lot of important content is hidden by the ad. Of course, simply clicking the "x" in the bottom right can easily hide that. However, it introduces some other problems... notice how that "x" is right above the box ad on that page. What if that ad extends outside the allotted area as well? Most of these ads extend simply by hovering over them. Closing the top one will extend the bottom one. Also, accidentally hovering over that top ad will extend it again. That's very easy to do since it's right below the site's navigation. I've done battle with these ads many times. It's not fun.

3 - Ads with Sound that Automatically Plays
You know those ads that say "Congratulations! You just won a Wii! Click here to blah blah blah"? Well, that's what I'm saying! It plays a sound or clip automatically. This forces a user to acknowledge the ad unless (s)he has the computer muted. Sure, maybe these ads aren't too annoying once, but they very rarely "happen" once. Usually, if I encounter one of these ads, I start to panic. It's likely that every single page on that site will have the exact same type of ad (or, in a lot of cases, the exact same ad). I already know that I didn't actually win a Wii, and even I did, I STILL wouldn't care. SHUT UP, ALREADY!

All that being said (or ranted; I'm not sure which), which of the above three ads is the most intrusive/annoying? Also, what other types of annoying ads are out there? Go!