Why limit your investment options when you can own a little of everything?

Exchange-Traded Funds (aka ETFs) make it real easy to diversify across a wide range of investments. Whereas before, you may have needed access to a margin, futures and Forex account, you now have access to similar features with just a traditional brokerage account or an IRA.

Here's how you can invest in everything.

Take Advantage of the Rally in Commodities

Cringing every time you go to the pump? Think gold could rise higher? Buy an ETF.

There are multiple ETFs that give you exposure to the commodities. For example, say you heard about the spring planting season being delayed. You could open a futures account and analyze hundreds of contracts or you could use your existing brokerage account and buy PowerShares DB Agriculture Fund (DBA).

In fact, you could easily create a basket of commodities with DBA, PowerShares DB Base Metals Fund (DBB), PowerShares DB Energy Fund (DBE) and SPDR Gold Trust (GLD).

There are also multiple funds that package stocks whose fortunes are tied to commodity prices, such as Market Vectors Gold Miners (GDX), a fund I recently added to ETF Trader.

Just make sure you don't confuse MOO with COW. One is Agribusiness (MOO), whereas the other is Livestock (COW).

Trade Currencies With Ease

Worried about that trade deficit with China? Think India's economy is going to rebound faster and stronger than ours? Want to trade Euros on a regular basis? No problem, just buy an ETF.

You have your choice of the Chinese Yuan (CYB), the Indian Rupee (ICN) and the Euro (EUR). And if a trip to the South Seas is in your future, you can even buy the South African Rand (SZR) or the New Zealand Dollar (BNZ).

Of course, the currency markets can move quickly. That's okay because you also have the option of being really aggressive with ETFs. For example, the Ultra Euro (ULE) rises at 2x the pace of the Euro, while the UltraShort Euro (EUO) moves 2x in the opposite direction. (Similar funds also exist for the Yen.)

Easily Buy Bonds

Have you ever tried to buy bonds through your stock broker? It's not easy. You have to know what maturity and credit rating you want. Furthermore, commissions are higher than that of stocks. Not to mention other factors you may want to consider, such as duration.

Alternatively, for the price of a stock trade, you could purchase an index of bonds.