5 examples of viral marketing

while sneaking around the web, i have found some interesting examples of viral marketing.
just want to share with you these.

(source: clickz.com)

Value Viral

• What it is: People share quality experiences with others.
• How it works: Joe tries product X and finds it to be very good. He then tells Jane to try it.
• Product examples: Hotmail, PalmPilots, Harry Potter books
• Web site examples: Amazon, Yahoo
• How to "make it viral": You can't. The products alone must be good enough to foster user chatter. "Tell a Friend" technologies do not make a product viral; they merely allow users to tell others about good products.

Guile Viral

• What it is: People try to "sell" to others in exchange for incentives.
• How it works: Joe tries to convince Jane to try product X because Joe may receive a reward if Jane tries it.
• Product examples: countless promotions, beenz, Amway, Tupperware
• Web site examples: Quixtar, MyPoints
• How to "make it viral": You can't. Users must feel that the reward is worth it and that the products are good enough to risk the possible displeasure of others. Simply adding a reward when the products are not of sufficient quality might result in user backlash against being "sold."

Vital Viral

• What it is: People want to share experiences with others, which requires certain products.
• How it works: Joe wants to share experience Y with Jane, and Jane needs product X to do so.
• Product examples: ICQ, RealPlayer, Macromedia Flash, Adobe Acrobat
• Web site examples: eBay, AOL
• How to "make it viral": You can't. Users must feel that the experience and the product are worth it to make a change for themselves, let alone to convince others to do likewise. Simply creating a user-to-user standard without making it worthwhile and enjoyable might only serve to inhibit adoption.

Spiral Viral

• What it is: People want to share funny, dirty, and/or interesting experiences with others.
• How it works: Joe wants to share experience Y with Jane because Joe thinks that Jane will also find it funny, dirty, and/or interesting.
• Product examples: numerous jokes, Superfriends video clip, Hampster Dance, Frog Blender
• Web site examples: Mahir Cagri's Home Page, JenniCam
• How to "make it viral": You can't. Success stories in this category were rarely intended to be "viral," rather, they were intended to be funny, dirty, and/or interesting. (The Superfriends email was originally sent to only seven people.) Also, this category is not well suited to push products.

Vile Viral

• What it is: People warn others of negative experiences.
• How it works: Joe tries product X and finds it very bad. He then tells Jane to avoid it.
• Product examples: Many failed dot-coms, Apple Newton, Olestra, "Plan B" book, Crystal Pepsi
• Web site examples: Real.com (for the RealJukebox fiasco)
• How to "make it viral": You can -- very easily. Simply create products that are of poor quality, are not designed with the user in mind, or are perceived by the user to be marketed in an underhanded manner.