The Albanian currency is called "Lek".  It is impossible to buy or use Leks anywhere else --  you cannot even exchange Leks outside of Albania, as it is a restricted currency.  They do accept Euro in some places in Tirana, and also Pounds and American Dollars. 

There are plenty of banks; at least in Tirana and in Durres there are also ATMs where you can get cash using a Cirrus or Maestro bank card.  Visa and Mastercard credit cards are accepted in some places.  The current (Dec 2008)  exchange rate is about 125 Lek to the Euro or Pound.  There are also money exchange shops and Western Union outlets for you to change your money; as a last resort, there are lots of men  walking around the city center waving big wads of money about -- you can go to them and haggle for a better exchange rate for your money.