Here's some more. Some you might like/need, some you might not.
Convert Center
Convert Center is so helpful with little unit equations you don't know of. It is also great for the big stuff as well. Since it is like every other converter on steroids this is a "I will use this often" site
http://www.convertcenter.com/
schoolr
A very nice website for the Student to find stuff. And by clicking more stuff you have some more features like awesome citation creators(Mainly why this is really nice)
http://www.schoolr.com/
newsmap.jp
A really cool way to look at and organise your news.
http://newsmap.jp/
Drumbot
Really nice for musicians. Has a Guitar Tuner, Drumbot, Metronome, and more. Plus you can run them off the site or by downloading them for offline use.
http://www.drumbot.com/
Still tasty
A site to help you figure out how long your food will keep and the best ways to store it.
http://www.stilltasty.com/
Cornell Method PDF Generator
Generates Cornell set-up pages that you can print off. Plus you can make it your own by adding a name or other things. No more whacked up line that isn't the right distance on your cornell notes.
http://eleven21.com/notetaker/
Itumz/
Your lists, Everywhere
http://itumz.com/
Hipcal
For you online calendar needs. Also lets you Subscribe, Import and Export through iCal
http://www.hipcal.com/
kuler
Helpful with Color themes. You can take pictures and create themes from colors within the picture.
http://kuler.adobe.com/
280 Slides
"Create beautiful presentations, access them from anywhere, and share them with the world. With 280 Slides, there's no software to download and nothing to pay for – and when you're done building your presentation you can share it any way you like."
http://280slides.com/
Evernote
Help save your ideas by writing them down.
http://www.evernote.com
Snipi
A way to help save and organise stuff you find, kind of like Evernote.(but has a Firefox Extension that you can use to drag drop stuff you want to remember)
http://www.snipi.com/tour/
Scrapblog
"Scrapblog is the easiest and most fun way to share and print your photos. With Scrapblog, you can create beautiful and completely one-of-a-kind layouts, share them online with your friends and family, and even print high-quality photobooks, greeting cards or postcards."
http://www.scrapblog.com/
Issuu
Great for online publications of magazines, books, catalogues, reports, and more.
http://issuu.com/