Pop-up ads are viruses
Pop-up ads are the scourge of the web -- they waste users' time and effort and erode their patience and trust of the Internet. Now Salon reports that one unethical company has taken it to an extreme by using pop-up ads and malicious coding to effectively deliver "malware" -- basically a virus.

"Thousands of unsuspecting visitors to a family entertainment site are discovering a cornucopia of unwanted, potentially malicious software on their computers -- the result of a pop-up ad campaign, a booby-trapped Web site, a compromised Web browser, and strange doings at a shadowy Los Angeles company.

[The ad] was designed to automatically redirect visitors away from Flowgo (no mouse click required) and to dump them at a booby-trapped site called KoolKatalog." "[A]ccording to virus experts, tens of thousands of Internet users have been back-doored by the KoolKatalog-distributed "malware," which they have added to their lists of malicious code for scanning. While researchers have not yet completely decoded all functions of the programs, they say two of the files" "attach themselves to victims' browsers and covertly monitor which sites they visit. Other components" "appear to enable the program's authors to secretly send updates or other files to the infected computer." This really takes the "viral" in "viral marketing" to an extreme.

Although most pop-up ads aren't intentionally malicious like in the KoolKatalog case, most are harmful in less obvious ways:

Computer viruses and pop-up (or pop-under) ads have a lot in common:
- They victimize unsuspecting, uninformed and unprotected users
- We've had to create specific utilities and software to protect users from them
- They interrupt users intended workflow
- They provide no value
- Users don't want to see either of them
- They are created by selfish, unethical people who have no regard for others
- When they "attack", they make users feel violated