This maybe completely obvious to the tech savvy user, but for someone new to mobile web browsing I found this indispensable. I don't surf the web on my phone so I never got into it.
For anyone who has tried to use the default bookmark for wikipedia on the Kindle it is almost unusable. I thought it was a complete joke the first time I used it, because the default wikipedia link is not formatted for mobile use.
After some research I just recently discovered that you need to use site compression like
Phonifier or
Skweezer. These sites transcode the html on the fly to optimize for mobile devices and make it so much more readable on the Kindle. They are both web based so nothing to install, just use as a proxy and enter the site you want to transcode. I like Phonifier because it is open source, but Skweezer appears to be the industry leader and used by Bloglines for instance. Skweezer has a bunch of popular sites in their directory so you don't have to enter the url, just select the links and then bookmark it.
I guess Amazon did not put these sites in the default bookmarks because they really do not want to encourage us to use the browser or Whispernet except to purchase books. But actually with site compression the browser on the Kindle is very useful because of the larger screen size than on most phones. Not for long sessions but in a pinch like at dentist office, car dealership, etc. I am sure people know of other ways to optimize mobile web browsing as well.