XE.com maintains a page with foreign currency symbols from around the world in conjunction with their other tools and services as a foreign currency trader. Exchange Rates UK also maintains a list of currency symbols along with ISO codes and Unicode decimal and hexadecimal values.
Aside from currency exchange sites and services, various standards organizations including the International Organization for Standardization also track and maintain currency codes and the corresponding Unicode typography symbols. Although on average they change little, with the adoption of the euro across Europe many countries dropped their currencies, and along with them the symbols and code. India, however, held a contest to design their new currency symbol, the winner of which they presented to the Unicode organization for approval and inclusion into the Unicode standard.