According to TI-BANK, there might be TI-Nspire CX prototypes around. TI has worked hard this time to make sure they do not go into circulation on sites like Ebay, where people can scam buyers with them, but we never know: one person can be enough to manage to leak such prototype calculator and fool people on online stores!

On Datamath.org, there's a picture showing one of the prototype during its boot sequence:
http://www.datamath.org/Graphing/Images/TI-NspireCX_P_BT_ZOOM.jpg

Here is how a normal TI-Nspire CX should look like (image from TI-BANK):
http://i23.servimg.com/u/f23/13/23/13/53/cx_ecr10.jpg

As you can notice in the first image, the small icon in the top-left corner is similar to the one on some TI-Nspire prototypes. Like the latter, those CX prototypes can NOT be upgraded using commercial OSes! This is why you should avoid buying them unless it is for collection purposes or messing around with them.

You can access the pages of the prototypes TI-Nspire regular and CAS models on Datamath.

When a new calculator is being designed, test copies of them are done for demonstration purposes, for example when there are teacher conferences and TI wants to advertise their products.

Those products are not the final versions, and since they're not intended for release, they generally cannot accept commercial OSes. However, sometimes, some people may decide to sell those on Ebay to make money, even if they're not allowed to release them.

Yeah basically if you see a TI-Nspire CX that is almost brand new for $80 on Ebay, it looks suspicious.

Ok I get it now

its made to get people interested and to bug test. Even though TI uses all of their calcs for bug testing especially production models

same thing. At least in my mind