For the majority of my math classes in middle and high school, a graphing calculator was a must. While the calculators were very useful to have, they were quite steep in the price column. After losing the TI-83 graphing calculator my parents bought me in high school, I had to save up my own money to buy the next one.
I can definitely say it hurt to personally drop almost $200 on a calculator that I used for only an hour a day at school and at home. Even then, the majority of the time I wasn't even using it for it's intended purpose.
Texas Instruments (TI) has yet to release any smartphone applications, probably due to the fact that they would lose tons of money. TI has long been the monopoly in the educational graphing calculator world, so creating alternative applications would diminish their sales, possibly giving rise to a new company—greedy bastards, huh?
Well, someone is finally sticking it to them.
While there have long been graphing calculator emulators online, the newly released jsTIfied is a more refined version of the rest. The TI-83+/TI-84+ graphing calculator emulator functions exactly like the real version.
In order to get the online calculator to work, you'll need to find calculator ROM images from anywhere online. You can easily search Google, which should provide plenty (here's a few you can use).
After that, you'll have to log in order to to export files, take screenshots, and transfer programs, but if you don't want to log in, you can just use the calculator online and all your data will be stored in your browser.
Check out the video below to see how it works.
You may not need an emulator if you already have a graphing calculator, but for something a little more fun you can always hack it to play Portal.
Know of any other great emulators? Let us know in the comments below.