Trading currency is a speculative investment. Investors attempt to buy and sell currency at the appropriate time in order to take advantage of changes in the exchange rate. If an investor thinks that a currency will become more valuable relative to the currency that his money is currently in, he might want to convert to that new currency, wait for the change to take place and then convert back. Of course, this is a very risky investment because there are no guarantees as to how currency values will change.
Investors can also purchase CDs from foreign financial institutions. These CDs make it possible to invest money at interest rates that may be more favorable than current domestic rates. However, it is important to remember that exchange rate fluctuations will also need to be factored in when the money is converted back to the native currency.
The value of precious metals like gold, silver and platinum is rooted in that fact that supply is limited and demand is ongoing. However, prices fluctuate, and, because money invested in precious metals does not earn interest, investment opportunities are limited.
Gold is primarily seen as a hedge against inflation or poor stock market performance. This is somewhat based on past observation, so it does not guarantee that gold will become more valuable during economic struggle. Investment opportunities for individuals include the stocks of gold-producing companies and mutual funds that allow for investment in several companies in the industry.
It is important to keep in mind that precious metals do not have any intrinsic value. While the value of stock is based partially on its expected future dividend stream, and real estate's value is based partially on its ability to generate revenues through rental, precious metals have value only because (and as long as) other individuals desire them.