5^i = -0.0386319699339353+0.99925350682348i
i(54i-3i^3)^5 + 9i - i^i^i + 3 = 3+601692067i
Interpreted Formula: ((((UNKNOWN(((54*i)-(3*(i^3)))))^5)+(9*i))-((i^i)^i))+3
0i + 4i - 0^0 + 0^i - i^i^i^i^i^i = -1.20787957635076+4i
i/0 = NaNNaNi
i^2i^3i^4i^5i^6i^7i^8i^9i = i
i^(2i*3i*4i*5i*6i*7i*8i*9i) = 1

I have no idea if any of these are right or wrong, but it seems to handle all sorts of weird things. (The last two seem contradictory, though.)

ryos wrote:

Interpreted Formula: ((((UNKNOWN(((54*i)-(3*(i^3)))))^5)+(9*i))-((i^i)^i))+3

Well that one is obviously wrong, because it thinks i() is a function - I shall have to teach it otherwise

I hope to extend the functions it knows to sin, cos, sinh, etc etc

I typed
5+6[ENTER]
and the text disappeared.

Isn't it supposed to perform the calculation with [ENTER]?

Very nice calculator. Here's something that I think might be weird, but I could have easily made a mistake.

Ryos's post made me decide to try out i^i. Its answer for that is ~0.2 + 0i.

It's a standard identity that e^(iθ) = cosθ + isinθ.
Therefore, i = e^(i*π/4)

Substituting this into the original gives [e^(i*π/4)]^i.
Using the laws of indices, we can the turn that into e^i²π/4 = e^-π/4.
But then putting that into the calculator gives you ~0.7 + 0i, even though it's equivalent to i^i.

Have I gone wrong somewhere?

Slightly newer version (v0.91). Should be able to type in e^(-pi/4) and it figures out the right order of calculation.

I also added a "cis" format button so you can see the result in polar form. Fun with e^() type entries.