I don't frequent a lot of websites but the ones I do visit, I visit a lot. I know the meme is for A website but here are several sites that I couldn't live without.
Pathfinder SRD - This website has everything in the player handbook & the bestiary. It also has a bunch of the 3.5 modules that have been updated to the 3.75 rule set. This site comes in very handy when we are playing D&D because it's much faster to just point & click for my info, even though I have the PHB. I think the website is even more valuable for DM's because you have all the information in one place, rather than having to flip through 2 or 3 books to find it.
The Realm of Covetedness - This is Rachel's blog & it's how I get my Rachel fix when I can't visit her, which is most of the time. She needs to blog more...and maybe post some nudes.
Facebook - a good majority of my free time is spent on Facebook, when I am not taking care of my kids or playing D&D. I like being able to see what my family and acquaintances are up to & letting them know what I'm doing without having to contact them all individually. It really takes the socialization out of socializing and I'm ok with that. I can choose what I want to respond to and what I want to ignore - PERFECT! It also has a lot of stupid games that are quite easy to become addicted to, like Bejeweled Blitz and FrontierVille. Which, if you're on Facebook and you use FrontierVille, hit me up 'cause I need some neighbors.
Robot Unicorn Attack - Rachel's daughter had this link posted on her Facebook a few weeks ago and I friggin' LOVE it. Not only do you get to play a Robot Unicorn that has special rainbow sparkle powers but there is also an Erasure song playing throughout the game. That's a WIN in my book any day of the week!
Blip.fm - This is a cool site that lets you create your own "radio station" and you can share what you are listening to via Facebook & Twitter updates. You can also subscribe to other "DJs" and it's a great way to discover new music. This is my DJ page.