I am trying to develop a method of making my site both highly useful and viral. These are the ideas I have come with so far:

- Allow people to raise questionaires which they email to their customers to research the market. (My visitors customers is exposed to my site)
- A user can create a text based puzzle game on my site which they email to a friend for them to answer the puzzle.
- Someone answers a quiz, if they get a high score they are considered an expert which they show off to their friends or colleagues.

Any other suggestions please?