Ladies and gentlemen I have found the mother of all mathematical resource sites.
Wolfram MathWorld

This site is the be all and end all of math sites. You'll be geeking out for hours on this site if you have a love of math. It is choc full of formulas and diagrams, some of which are interactive. It is mind-boggling when one considers the range of topics this site covers, no matter how simple or complex. And they don't skimp on the details either, with each concept (at least those I've read) thoroughly and clearly explained while keeping technical verbosity to a minimum. That being said, one still has to be familiar with mathematical terminology, thankfully each and every one is described (via links) and examples provided.

I also found a cool open source math tool that is great for building visual aids for math concepts:
GeoGebra

Once you download and install the tool, you can use it to create you own interactive applications to illustrate mathematical concepts and problems. There is this one site owned by Micheal Horvath with a number of .ggb files available for download. Check them out at:
http://www.geocities.com/Area51/Quadrant/3864/sketchpad.htm

I have used his .ggb files on Bezier curves to clarify the concepts. I have a far better grasp of Bezier curves now than I ever did before.

I encourage anyone even remotely interested in math to check these sites out. You won't be disappointed.

Edit:
This just in . There is also a GeoGebra wiki with tons of resources. Enjoy.

This post has been edited by dimumurray: Aug 14 2008, 02:13 PM

Whoa, I found that website *ages* ago! That doesn't stop it being the best website for mathematics though. (even though I use Wikipedia mostly..)

GeoGebra looks nice (the screenshots), even though it's only geometry - I might check that out some time soon. Thanks for the link!

I've used mathworld a lot and it's immensely helpful, especially for more obscure stuff you can't find anywhere else. Wikipedia also usually has a lot of articles on the same stuff and with different focuses, but nothing has the depth and breadth of mathworld. Mathematica is also a great piece of software especially for really complicated math though it takes a while to learn.
Another great site with a lot of applications to solve, factor, etc equations is QuickMath it actually uses mathematica I think, but in any case it's really helpful when you want exact solutions to problems or you leave your calculator at work.

Very, very nice find. This will definitely help out when it comes to school. I've been used to just having to ask people for formulas and whatnot.

Thanks!