A few definitions, with demonstrative images, that I continually revisit as I think through mass engagement platforms. Universally useful precedents in experience design.

1. 6
Some Lego Pieces

2. 7
Soliciting and sustaining massive
participation...Mufucka.
Engagement

3. 8
A prizing model that spurs social passalong.
Recruit your friends, get paid when they sell.
Affiliate Modeling
Karmaloop.com
Groupon
Avon
Tupperware

4. 9
Present a problem to be solved by a group for a
big payoff. Usually, superfans work and casual
fans benefit (without effort).
Cooperative Unlock
The Dark Knight campaign - Joker face reveal

5. 10
Create a sandbox for a group to build a piece of
work together. May require rabid fanship,
sharp segmentation.
Cooperative Build
Johnny Cash Project

6. 11
Whether individual or co-played, require evidence
of finding something for a big payoff.
Scavenger Hunt
New Balance Urban Dash

7. 12
How: two prompts are delivered linearly. Players
identify differences. Speed or accuracy to win...
Matching Games
Louis Vuitton Spot the Difference videos

8. 13
Present a branched story with more options than can
be simultaneously followed, to give the perception of
user choice.
Choose Your Own Adventure
DC Comics & X Chuck Taylor (Converse) comic book
http://www.gifmemoreparty.com/

9. 14
CYOA structure, but requiring consensus on
decisions among multiple parties. Can also be
toggled to a voting mechanic.
Choose Ya'lls Own Adventure
Eve Online MMORPG

10. 15
Show players’ status. Sometimes a good idea.
Sometimes not.
Progress Bar

11. 16
Send a signal that amounts to a user-specific call
to action. Requires the sense of 1:1
communication: user(s) must feel targeted.
Batphone

12. 17
Train audiences to interact by amplifying others'
successes in real time. Whether a slot machine
hits for $5 or $50K, the alarm is the same.
Ubiquitous Proof

13. 18
Telling a story over time, space, and channels.
Programming

14. 19
Release information in distinct packets, on a
schedule determined solely at programmer's
discretion.
Phased Reveal
Memento

15. 20
Up the replay factor and discussion-worthiness of
a given execution by putting more stimulus into it
than can be perceived at once.
Multiple Focci

16. 21
Jack stuff and situations from the other worlds to
bring to life around the brand.
World Jacking
Prometheus/TED video

17. 22
Mix characters from disparate contexts to produce
surprisingly unified "chords."
Strange Bedfellows

18. 23
Create intimacy by creating physical goods for
people to interact with.
Tangible Assets
True Blood campaign

19. 24
Make executions more or less prone to interaction
(depending on what you want).
Dials and Levers

20. 25
Add a countdown clock to spur perception of
urgency/scarcity. See: "Last call." "limited time
only." "This week only."
Time Sensitivity
Halo 2 ilovebees campaign

21. 26
Restrict access to a physical boundary, to
encourage visitation, group/exclude audiences, or
solicit data.
Location Sensitivity
Airwalk Pop Up Shoe Store

22. 27
Require proof that something happened at a certain time.
Today’s Newspaper