Greek Unicode and Inkscape

To get Greek letters in Inkscape, go into text mode and type Ctrl+U and the 4-digit unicode for the desired Greek letter. (See this.)

Greek letter	Lower case	Unicode	Upper case	Unicode
alpha	$α$	03b1	$A$	0391
beta	$β$	03b2	$B$	0392
gamma	$γ$	03b3	$Γ$	0393
delta	$δ$	03b4	$Δ$	0394
epsilon	$ϵ$	03b5	$E$	0395
zeta	$ζ$	03b6	$Z$	0396
eta	$η$	03b7	$H$	0397
theta	$θ$	03b8	$Θ$	0398
iota	$ι$	03b9	$I$	0399
kappa	$κ$	03ba	$K$	039a
lambda	$λ$	03bb	$Λ$	039b
mu	$μ$	03bc	$M$	039c
nu	$ν$	03bd	$N$	039d
xi	$ξ$	03be	$Ξ$	039e
omicron	$o$	03bf	$O$	039f
pi	$π$	03c0	$Π$	03a0
rho	$ρ$	03c1	$P$	03a1
sigma	$σ$	03c3	$Σ$	03a3
tau	$τ$	03c4	$T$	03a4
upsilon	$υ$	03c5	$ϒ$	03a5
phi	$ϕ$	03c6	$Φ$	03a6
chi	$χ$	03c7	$X$	03a7
psi	$ψ$	03c8	$Ψ$	03a8
omega	$ω$	03c9	$Ω$	03a9

Note the jump in unicode values between rho and sigma. This is not an error; we have skipped a special form of sigma used in the Greek language. Here is a PDF of this document.