A common technique used by websites which very few people would ever look at is to purchase domain names with only one letter of difference from already popular websites. Many companies have picked up on this and picked up the DNS for the most common mispelling or mispellings of their name. A few of the more interesting examples follow.

LivJournal.com Rather than being Liv Tyler's personal website, as the name would imply (rimshot), this site is actually a poorly made refresh trap. It attempts to refresh to the URL of a Dutch porn site, but makes an error in HTTP syntax by putting the URL in quotes. Consequently, it doesn't work... it eventually leads to "Amatuer Videos" sic, then "Hanky Panky College", its final destination.

Gogle.com actually refreshes to Google. Hah. (yerricde informs me that Gogle used to be its own affair, but Google bought it.) So does Gooogle.com. Only by trying Goooogle.com do we find an outside link, to one of those damn "Find Everything You Want On The Internet!" sites.

Goole.com (vuo) is a portal to Ask Jeeves.

Exite.com (yerricde) is owned by Excite. Exit-e.com is a German site with no content as of yet.

Whitehouse.com (Oolong) is porn, porn, porn.

Whitehouse.net (Oolong) is much better, featuring a humorous parody of the real White House site.

Whitehouse.org (Nero) is a rather leftist, anti-Bush site. Also quite interesting: they sell thongs.

Yaho.com has similar results. Yahooo.com belongs to Yahoo!. Yhoo.com is an "Under Construction" page.

Hitmail.com goes roughly nowhere. The entertainingly named HoMail.com is not taken. HTMail.com is a legitimate business, although they're spam purveyors. Hotmal.com endeavors to sell you "the USA Gold Card".

Slashdot Variations (Servo5678) yield all sorts of interesting things, like ads, porn, deadlinks, and sites containing Slashdot in frames. Try salshdot.org and sla5hdot.org for starters.

Anglefire.com is the "Adult Friend Finder!" Exciting, eh?

Geocity.com is owned by 1000search.com, which likes selling all manner of useless garbage.

FortuneCities.com is MegaGo, which is a search engine. It even works. What kind of search engine does stuff like this?

NetworkSolution.com is a security information site. It sounds fairly legitimate.

Micorsoft.com (Servo5678) is filled with annoying popups, courtesy of searchport.com. Microsfot.com, more interestingly, links to alternative software to Microsoft's, using the clever acronym MICRO Site For Other Technologies.

NYTime.com sports the "Verisign Is A Bad Company" spiel. I do wonder who gave them their domain name, though...

/msg me if you want to add to this.
Thanks to all who contributed (names appear at the beginning of submitted paragraphs.)