Have there been efforts to introduce non Greek or Latin alphabets into mathematics?

To add to some of the letters and alphabets mentioned, in set theory, the Hebrew letters $\aleph$ and $\beth$ are used.

It is common to, as you mention, use specific variables letters for specific purposes. More obscure, foreign letters are probably seldom used simply because they have no need to be introduced. Mathematicians already they have two alphabets to choose variables from!
However, for things that have specific purposes, like constants or special functions, cannot be given the same variable letter without causing some confusion.

In the 1960's, a fellow at IBM by the name of Kenneth Iverson created a new mathematical notation that originally held the name "Iverson's Better Math".

He published it in a book called A Programming Language, and since IBM wasn't too keen on the internal nickname, the notation itself came to be known as APL. (Iverson didn't mean programming language in the computer programming sense, though an interpreter was in fact soon implemented, and you can now execute APL on a computer.)

You can see the symbol set used in this on-line APL interpreter, and you'll note that there aren't too many greek or latin characters at all. (The iota generates a vector of sequential integers , rho reshapes the rows and columns of an n-dimensional matrix, alpha and omega are used for defining functions of one or two variables).

APL relies heavily on function composition, and often variable names are not needed at all. The number we call pi is represented by a circle (which also can be used for all the trigonomic functions), and one of those symbols does the work of e and log.

It also uses an explicit multiplication sign, which means any word at all can be used to represent a variable, whenever you actually do need one.

Iverson's book is online at http://www.jsoftware.com/papers/APL.htm if you're interested. There's also a shorter article called Notation as a Tool of Thought, which I believe was his Turing Award lecture.

This was a serious effort to reform mathematical notation, and it was actually quite popular at the time. You could even get a typewriter with the APL characters (in fact the character set was partially chosen based on what you type on an IBM typewriter). But the commercial book publishers of the day had trouble with all those new characters, and of course it has a rather steep learning curve.

People still use APL today, especially in the financial markets, along with modern variations like J and K that stick to ascii symbols while managing to remaining just as cryptic.

I'm not sure that's exactly mainstream acceptance, but there you go :)

In advanced number theory arithmeticians have introduced the russian letter Ш, pronounced "shah".
But this is very localized.

Apart from the Greek alphabet, the only different alphabet I know of used in a Latin environment is Fraktur, popularly known as Gothic.
It is massively used in algebra for ideals in rings.
Actually, essentially all standard references in commutative algebra and algebraic geometry make use of Fraktur: Atiyah-Macdonald, Dieudonné-Grothendieck's EGA, Görtz-Wedhorn, Hartshorne, Jacobson, Matsumura, Qing Liu, Shafarevitch, Zariski-Samuel,...

Edit The $\LaTeX$ command for Fraktur is $\text {\mathfrak}$. For example:

Let $\mathfrak p$ be a prime ideal, $\mathfrak q$ a primary ideal and $\mathfrak a,\mathfrak b, \mathfrak c \:$ arbitrary ideals of the ring $A$, then...