You have $200. How do you drive traffic?
You have $200. You can spend it on whatever you want. How would you drive traffic most effectively? Content site OR web application.
Stupidly, I forever put off doing that one!
Do you mean this person owns a list and spent $20 somehow sending email to this list? How does this relate to the $180 bracelet?
Please excuse my ignorance :-)
But with only $200 you want to make sure every dollar -- every penny -- counts towards getting action. So I would use it on the most targetted ads I could get. For most fly-by-night web apps that only have a $200 ad budget, adwords would be the best way to do this.
You can get more sophisticated if you want, but that's all I did. I ended up getting around 4000 seed users for a Facebook app I built in '08 this way.
You can read it for yourself here:
However, it would be foolish to neglect the free and (arguably) better way to drive traffic: SEO.
Patio11 has a blog full of information about enhancing your SEO, creating targeted content, and building your site to generate a lot of traffic without the need to spend money.
Edit: Start Here - http://www.kalzumeus.com/greatest-hits/ I know it seems like a ton of stuff to read, but it is absolutely worth it.
Reddit has good CPC and engagement rates, so long as you have content or an application that appeals to that crowd. (See Gabriel Weinberg's post on the topic).
StumbleUpon has a more mass-market appeal, but relatively high cost-per-view with low engagement.
Adwords is expensive unless you spend a long time honing in on niche keywords. Even then it is expensive.
There was a great post on ASmartBear this morning (guest post) about how effective cold-calling can be. And that's essentially free (not counting your labor hours).
Pud has a great write-up on this topic: http://pud.com/post/5239917032/users
This is something I struggle with too, so I'll be interested to see the other responses.
The important theme online though is to leverage someone else's audience.
Adwords, SEO are all leveraging Google's audience.
Approaching bloggers in that space is leveraging on those authors' audience.
Finding complementary products and offering them a commission is another way of leveraging an audience. There were a few interviews on Mixergy where SaaS makers deliberately integrated Freshbooks or Shopify because it brought them customers.
If not, then the answer is it depends. It depends on who you're targeting, and on what action (reading an article? sharing it? signing up for a product or newsletter?) defines success.
Example: Mint has infographics because people who love numbers will love those pictures. So, they pay the cost of someone designing them.
A social network like MySpace/Facebook wouldn't attempt this because they are not looking only for an audience that love numbers.
$100 on a table at your customer's industry event