Found over on Search Engine Land: 2007 Guide to Linkbaiting: The Year of Widgetbait.

A little background from Wikipedia before you jump on over:
Link bait is any content or feature within a website that somehow baits viewers to place links to it from other websites. Attempts to create link bait are frequently employed in the overall task of search engine optimization. Matt Cutts defines link bait as anything “… interesting enough to catch people’s attention.” [1] Typically, users on bulletin boards, newsgroups, social networking websites, or blogs place a link to a website in some copy that further encourages another member or visitor to click. It can be an extremely powerful form of marketing as it is viral in nature.

The quantity and quality of inbound links are two of the many metrics used by a search engine ranking algorithm to rank a website. Link bait creation falls under the task of link building, and aims to increase the quantity of high-quality, relevant links to a website. It is considered to be a white hat optimization method almost universally. Part of successful linkbaiting is devising a mini-PR campaign around the release of a linkbait article so that bloggers and social media users are made aware and can help promote the piece in tandem.

Although there are no clear-cut subdivisions within link bait, many attempt to divide them into types of hooks. This is a short list of some of the most common approaches with brief descriptions:

  • Informational Hooks – Provide information that a reader may find very useful. Some rare Tips and tricks or any personal experience through which readers can benefit.
  • News Hooks – Provide fresh information and garner citations and links as the news spreads.
  • Humor Hooks – Tell a funny story or a joke. A bizarre picture of your subject or mocking cartoons can also prove to be a link bait.
  • Evil Hooks – Saying something unpopular or mean may also yield a lot of attention. Writing about something that is not appealing about a product or a popular blogger. Provide strong reasons for it.
  • Tool Hooks – Create some sort of tool that is useful enough that people link to it.

What is a Widget?
A Web Widget is a portable chunk of code that can be installed and executed within any separate HTML-based web page by an end user without requiring additional compilation.

Web Widgets can be utilized by end users to enhance a number of web-based hosts, or drop targets. Categories of drop targets include social networks, blogs, personal homepages, and operating system desktops.