i raised to i?

i=e^i(pie)/2,

i^i=e^((i*i)pie/2)

    =e^(-pie/2)
there can be many more answers.increase the angle by 2 pie. 

let exp(.)≡ e^(.),iⁱ =exp(i((π/2)+2nπ))ⁱ =e^{-((π/2)+2nπ)}, where 'n' is ANY INTEGER