Is Pi plus Euler's Number Rational?

Open Question
It is not known whether the sum of $\pi$ (pi) and Euler's number $e$:
 * $\pi + e$

is rational or irrational.

Progress
By Transcendence of Sum or Product of Transcendentals, Euler's Number is Transcendental, and Pi is Transcendental, at least one of $\pi + e$ and $\pi e$ is transcendental.

Also, see Schanuel's Conjecture Implies Irrationality of Pi plus Euler's Number.