Goplat, from United-TI, who also idles in both #omnimaga and #tcpa IRC channels on EFnet, has released a TI-Nspire emulator, shortly after having decrypted the TI-Nspire OS. Since it is in very early stages, it can only run one version of the OS, which is TI-Nspire CAS OS 1.1.

Quoted from him at United-TI, here is what was said:

I've been making an emulator/debugger. It's very incomplete and non-usable, but it can now run at least one version of the OS (CAS version 1.1).

To try it out, first run: "nspire_emu /B=<filename of BOOT2 dump> /G /X /C /W=<filename of flash image to create> /O=<filename of TI-Nspire.tnc>" to install the OS and create a flash image. When that finishes, run "nspire_emu /B=<filename of BOOT2 dump> /G /X /C /R=<filename of flash image>" to run the OS.

Some caveats:
Newer OSes don't work because of something about an "unrecognized keypad"
The old non-CAS OS just crashes (I think this is because of the lack of BOOT1)
No USB emulation
Runs too slow with instruction translation off, runs too fast with it on
Debugger acts strange when translation is on, and is pretty minimally functional in general
Still, it's a start. You can enter the debugger with ctrl-D.

Source: http://www.unitedti.org/index.php?s=&showtopic=8191&view=findpost&p=138702

Since one year ago, United-TI has been forcing guests to register in order to download files and screenshots attached to their forum posts, we have decided to attach the emulator download directly in this post. Guests can download it fine, like any of our other file attachments posted outside the Randomness section of the forums, and here is the download link:

http://www.omnimaga.org/index.php?action=dlattach;topic=1209.0;attach=382

Remember we will not provide any links to ROMs or illegal downloads on our forums. It is your task to acquire one. More info about TI-Nspire cracking developpement can be found at the following URL:

http://www.unitedti.org/index.php?showtopic=8191

Nice, I'll update file in the news when I get some time, for people who don't have a UTI account.

I am curious if it could enable the possibility to do an emulator to play HP-48G and HP-49G ASM games on the TI-Nspire. Both uses ARM processors, IIRC

My friend Bwang says that there is a possibility of running Linux on it :O

hmmm, maybe someone should try to port it! like make some drivers and such

Random thing...there is an iPod touch app that emulates the HP48GX...but still no TI-83+...
So if we can make all these cool emulators and such, why has nobody attempted to make an iPod emulator?

Nice, I assume it's for the latest version?

ah ok missed that part