I've been brainstorming a lot for the past couple of months, like many here, on ways to introduce people to the bitcoin economy in a way that promotes organic growth.  I think I've come up with an really fun idea.  Here are my premises:

1. Purchasing coins via exchanges is currently too laborious for most people.
2. Bitcoins purchased via exchanges are less likely to be spent than coins acquired via other methods.
3. If something feels like a game, many more people are willing to engage and ignore trivial difficulties/inefficiencies.

My solution: The Bitcoin Challenge.  This will be a website that will, for the first part, simply explain bitcoin and then walk the user through download/setup of the bitcoin client.

The second step will be to recommend to the user a variety of bitcoin sites that can help them earn their first coins.  I've already spoken to many sites about partnering with me.  These sites will be ones like forbitcoin, bitgigs, bitcoinclassifieds, biddingpond, etc.  Maybe we'll even include that bitcoin dare site I saw someone writing about on this forum.  The point is that I think it is best to get your first coins by selling your own services or stuff you have lying around your house.

The third part is the carrot.  I'm working on creating a "newbie package" that the newbies can purchase with those first coins they earn.  It will likely include some combination of: An exclusive t-shirt (saying something like "Member of the bitcoin economy", but awesome-er), a physical bitcoin (probably from coinedbits.com), and maybe a btc sticker.  I'd love to give this to them for free, but I can't really swing that. Plus they'll have coins, so it will probably suffice to sell them this stuff at cost.

So the end product is a user who knows how to earn coins, has been motivated to do so with some cool exclusive stuff, and will now be a walking/talking advertisement for the movement.

Problems to overcome
1.  We have to make the "newbie package" something that would actually be desirable enough to motivate users.  I'll likely solicit the community's help in the design of the shirt, but I think we can do it.

2.  The coins to purchase these newbies' goods/services will have to come from those of us who already have coins.  I can imagine a scenario in which we get a bunch of newbies to post their goods/services but no one buys them.

3.  How to make newbies aware of the challenge? Paid Google advertising?  How to raise money?

4.  There are lots of logistical issues to be sorted out.  How do we track/monitor user progress in the challenge?  I would rather this newbie package be something available only to true newbies, but can't think of a way to regulate that.

5.  Need a name/url. Bitcoinchallenge.com is taken.

So, community, what do you think?  Anything you can think of to make this even more game-ish?  I really think that is the key here.  Let me know your feedback.