By having a well designed site with lots of interesting and unique traffic can increase the chance of people bookmarking a site,or using the address bar on their browser to type in your address bar.
Having a short easy to spell domain name can increase direct traffic.
^Indeed, I think this is how Ask.com get a good percentage of their traffic by paying free and open source software makers and websites to bundle the Ask tool bar with their free software like CCleaner in exchange for some advertising revenue the tool bar generated for Ask from Sponsored links on Ask.com search result pages. A lot of free toolbars come bundle with a lot of bookmarks and links to their websites, and they are not removable in many cases.
Last time when I bought a new computer from HP, it came with a bunch of bookmarks to Ebay, AOL, and a bunch of other websites located on the desktop or in folders on the desktop.
I guest Firefox, and Internet Explorer also gets some traffic from pre-bundled bookmarks in the web browser and embedded links in their applications.
I also notice many freeware makers don't include help files, but a bookmark to their website FAQ, forum or help section when you click on the help shortcut in the program, or startmenu folder for the program.
I use bookmarks everyday to visit forum promotions, my own websites, gmail, and countless other websites on a daily basis.
I read on an Marketing blog that people who bookmark your website are the most loyal visitors and are most likely to return on a regular basis or buy stuff from you if you sell stuff.
But, Most people probably use the "Most Visited" tab which is available on Google Chrome. Speed dial tab for Opera, and top most visited tab in IE. Recently closed tabs in Firefox.
Bookmarks can also refer to social bookmarking, eg. Digg, StumbleUpon etc., and it's actually a booming area; SMO. It's increasing in popularity and a lot of traffic has been noted from these social sites, whether networking or bookmarking.
Twitter and "Facebook Share/Like" is probably the most popular place where people look for links trustworthy people "bookmarked/twetted" on from people.
It is sometimes a lot easier finding trustworthy social bookmarking members which post lots of links to good articles vs visiting random sites for articles on a specific topic.
I seen people also plug other people blogs on Twitter, and suddenly their blog gets a lot more traffic.
