I'm looking for a nice, quick online graphing tool. The ability to link to, or embed the output would be handy, too.
desmos.com It's by far the best.
Well, I am not sure where you want to embed the graphs, but Wolfram Alpha is pretty handy for graphing. It has most of the features of Mathematica, can handle 3D functions, and fancy scaling and such. I highly recommend it.
I really like Geogebra as a web based graphing tool (requires Java).
Here are the online tools I am using daily for plotting graphs and also graphing geometry:
Desmos (great usability, awesome features)
Plotlux (powerful plotter, based on fooplot)
Graph.tk (fast and easy plotter)
Geodrafter (graphing of simple geometric shapes)
Geoservant 3D (graphing of simple 3D objects)
Geogebra (powerful, comprehensive, but cannot be used commercially)
Sketchometry (geometric objects, interesting usability)
As soon as I discover new tools, I am updating my post.
I created a tool to plot graphics and published it several hours ago.
To use this tool you can use desktop computer to show graphics and listen income connections over the network.
Your target project can be run anywhere in any language in any platform - to update graphics just send data over the network.
I began undergrad as a math education major. I found Desmos extremely helpful for clearly displaying graphs with a user face that was simple enough for all my students to work. Combining this display with the Windows Snipping Tool lesson plans and handouts became easier to create.
Having switched majors/graduate with a math degree and working on a masters in math with a statistics concentration I really like using R. RStudio has a beautiful output; there are a few open courses on the DataCamp website for making charts and graphs in R. It's pretty neat.
For me I have been using Transum. It helps me showing quickly graph of any correct equation