First is it possible? If yes, how would I do it?[/list][/i]

Well it is possible but it would require writing an entire OS with CAS in mind.

I believe there is a project somewhere that is at least considering the possibility, but im not sure if there is any progress.

Well another question. Would it be possible to transfer a ti nspire cas os onto a normal ti nspire?

AHelper's GlassOS project aims to completely replace the TI-OS, and has a fledgling CAS. However, the math features aren't in a fully-useable state quite yet; they're currently going through another overhaul.

http://www.cemetech.net/forum/viewtopic.php?t=5932

nLaunch let's you do that with the nspire.

As KermM pointed out, the math features in gCAS2/3 aren't really on-par with usable. I just don't have unlimited time to work on all projects, so I use a round-robin system. Calc stuff is low on my list (from the recent Prizm development for contest #9) and Linux/Windows stuffs is my priority now. Don't worry, I will work on gCAS3 and get it in a state to be able to do more math (it currently does regular math just fine, just nothing with special operators, like sqrt, trig functions, etc.)

A lot of this could be wrapped up in good support for exponentiation and complex numbers.

Which requires a soft float library that is very tiny that can fit on the Z80. I have found SoftFloat (or something), which seems like the best bet. Right now, I need better floating point number support that is small enough for the Z80 in C.

How do I do that with nLaunch?

This topic on omnimaga goes into a fair amount of detail