Generating interest is required to get customers

Before any deal is closed, any sales process is started, any leads are generated, and people in companies need to get interested in the solutions you offer.
Without any interest not a single customer will show up, not any deal will be closed and no revenue will be made.

Getting their interest can be obtained in several ways:

Buy interest: Advertising
Many channels and many formats are available at different prices.
The problem is that advertising costs money and can be a waste of money if your advertising is not effective or has ineffective placement.
This is a mass media communication trying to purchase as much interest as possible with one action and expense.
The result should be any form of inbound marketing: visit website, email or a call.

Hope for interest: Public relations
Sending out press releases in the hope someone picks it up: journalists, bloggers or editors.
However this is a two step process: as after the media the people in companies still need to read about it.

This is a one to limited many communication with the hope it gets mass attention.
The result is registered as inbound marketing.

Gain interest: Content marketing
You publish a blog, you write comments on blogs, you write in a magazine
All this content generation has only one purpose which is to draw attention to your company or solutions.

This is a one to many communications, where the number of receivers can vary significantly.
Getting book marked can make a huge difference.
Again inbound marketing.

Reference interest: referrals
Your solutions are being referenced by third parties or by your customers.

This communication is beyond your control.
This is the best and the most valuable of any method to generate interest.

Clearly inbound marketing is the effect.

Review interests:
Your solutions are getting reviewed by magazines or bloggers.
There is a communication and level of influence from your side as you have probably addressed the reviewer for participating in the review. It is unlikely the reviewer will address your company if you are not the market leader.

The effect is inbound marketing.

Advocates generating interest
People are convinced or impressed by your solution and tell their friends, colleagues and peers about it.
You have no direct control over this communication however the content can be influenced or supported by advertising or published information (blogs or reviews).
This is the second best method after being referenced.

Inbound marketing is the result.

Press for interest: Selling
By calling and emailing or setting up meetings you press people to give you some interest.

This is a one to one communication thus requiring a lot of time.
This is clearly outbound marketing as the salesman takes the action and sets up a conversation directly with the potential customer.

Negative news
Even negative news brings interest and spreads faster than good news.
As the negative news is normally not communicated by your company, someone else has send out negative news or a negative impression about your company or solutions.
Negative news is better than no news.

The effect is inbound marketing.

As always in marketing by just applying a single method will probably not work. However a combination with the right mix will probably achieve to generate the optimum interest for a certain cost (the budget).

What other means of getting interest from potential customers exist in B2B?
What does your company apply or is good at?