Anyone remember eTour? The site whose tagline was "Surf the Web Without Searching" didn't survive 2001's dotcom crash. StumbleUpon is Web 2.0's eTour and it's an absolutely fantastic way to wander through websites that potentially interest you. There's no typing, there's no "links" pages to seek out. There's not much effort on a user's behalf at all.

• To use StumbleUpon, you must download an add-on to your toolbar that lets you give sites a thumbs-up, thumbs-down and click "Stumble!"
• Submit your site to StumbleUpon by clicking the thumbs-up button when you're viewing your homepage. If you are the first person to bookmark your site, you'll be prompted to give it a title, briefly review it and fill out some other information about its content.
• If you've said your site is about technology, users who have specified technology as one of their interests will potentially be directed to your site when they click "Stumble!" You may only pick one topic.
• The tags you give your site will also influence traffic. Unlike topics, you may include multiple tags.
• There is also an automated system whereby StumbleUpon reads a page's text and decided what it's probably about.
• The system sometimes gets it wrong (pages containing mainly graphics are obviously hard for the categorizer). Users, however, can report mistakes if they feel a site has been categorized inaccurately.
• Getting noticed on StumbleUpon depends on whether users identify your page as one they enjoy by using the thumbs-up button. The more people who identify your page as thumbs-up-able, the more traffic StumbleUpon will send you.
• Also, if a user comes across your site and really doesn't like it, they can click a little thumbs-down button on their tool bar before leaving, demoting your site's status on the StumbleUpon network.
• Members can join StumbleUpon Groups and contact others on the site, although these social features aren't nearly as interesting as StumbleUpon's addictive ability to store and present websites that people like.
• Additionally, although it is a free service, members can upgrade their accounts to the status of "sponsor" by paying twenty U.S. dollars per year. Sponsors have access to extra features, such as the ability create new groups and to keep messages in their inboxes for longer.
• One could argue that there's a psychological advantage to having your site discovered by a Stumbler. After all, they've told a program what they like, and the program has presented them with your site. Hence, people are somewhat programmed to believe that they're going to like what they see.
• StumbleUpon is linkbait's tool of choice. When stumbling, you'll often find yourself arriving at pages well within a site. Rarely are you directed to a homepage.

This site is so popular that searching for any kind of keyword will often display a Wikipedia result in Google's top ten.

• Tacky as adding links to your sites can get, if your site really does have something to contribute, go ahead and post your link in a Wikipedia article's External Links section.
• The wiki aspect of these online encyclopedias is dangerous because you may find people writing things about you that you don't like.
• Also, if your website is not the strongest page on the net, your entry on Wikipedia could well rate ahead of your own site for your specific keywords. Thus, it is smart to make sure that anything said about your interests on this site has as good of a balance between "true" and "complimentary" as possible.
• A surprising number of internet users don't fully understand the concept of a wiki and many have no idea that anybody can edit one, let alone write for one.
• Posting an advertisement that is posing as an article is pointless. It will be deleted. When you're writing unique content about your business, try to write it from the perspective of an outsider who has nothing to gain from the article appearing on Wikipedia.
• Your main professional aim on Wikipedia should be controlling what is said about you. Their links are far too influential for you to ignore Wikipedia's content, especially given the public's misunderstanding of its liberal editorial policies.

A first reaction to LinkedIn's blurb is to wonder just how experiened and how professional the members of this site actually are. After all, LinkedIn's worthiness somewhat depends on the calibre of its seven million users.

• Clicking "People search" and typing in a common last name will provide a good list of people, their industries, companies, positions and locations. And, wow, this site is not filled with spam and idiocy!
• The majority of people on LinkedIn are true professionals. Thus, there are definitely marketing opportunities available here.
• The process of promoting a business on LinkedIn involves getting recommendations from other people (who must have LinkedIn profiles themselves). When you receive a recommendation from someone, the fact that they recommended you appears in your profile. The only odd thing about this is that the recommendations do not come with the names or statements of the people who provided them.
• You can search through professionals in specific areas (and be listed, if you have the adequate recommendations),
• Job searches for job-seekers and a candidate search for employers and recruiters is also available.
• You can also view members who graduated from your school, people with specified skills and people from a particular area of the world. And yes, this site is popular enough to be truly international. Looking for an engineer in Denmark? Look no further.
• Oh, how wonderful it is not to have to provide one's relationship status or a list of "who I'd like to meet!"
• Gain visibility on a site where everyone is there for professional purposes. You can use the site to either find potential business associates, or someone may find you and your services instead.