AMSAT has a nice web site, full of information on amateur radio satellites, tools for tracking them, news, etc.
My gripe with the site has to do with the page style. The background image is something called "flannel", which is a bunch of fine black stripes on a white background. For me, it is too much white. To make matters worse, on some monitors, the stripes do some sort of flickering. Not Moire lines, but flickering, probably due to some video card setting I have wrong.
Rather than impose my tastes on others, I wrote a goofy little Greasemonkey script to change the background:
// ==UserScript==
// @name BlueAmsat
// @namespace http://userscripts.org/users/57521
// @description Change the AMSAT default background to blue
// @include http://www.amsat.org/*
// ==/UserScript==
document.body.style.backgroundImage = "none";
document.body.style.background = "darkblue";
You can install it directly here