DIAMONDS Trust (DIA:AMEX)

This popular ETF Tracks the Dow Jones Industrial Average, a benchmark of 30 blue chip stocks selected by The Wall Street Journal. The index is highly subjective and rather antiquated in its formula but serves as a good barometer for very large old-line US companies.

iShares S & P 500 (IVV:AMEX)

Barclays’ slightly less expensive version of the SPDR tracks the S&P 500 index, which is widely regarded as the standard for measuring large-capitalization U.S. stock market performance. Some selectivity by Standard & Poor’s surrounds an otherwise methodical list of the 500 largest traded firms.

Total Stock Market VIPERs (VTI:AMEX)

The Vanguard Group’s core portfolio ETF tracks the Wilshire 5000 broad market index, which is one of the broadest index for the U.S. equity market, measuring the performance of the vast majority of all U.S. headquartered public companies. Considered an excellent proxy to the US economy as a whole.

iShares SmallCap 600 (IJR:AMEX)

Tracks the S & P SmallCap 600 index, which measures the performance of the small-capitalization US companies.

Consumer Services Select Sector SPDR (XLV:AMEX)

One of the many sector ETFs from S & P, which tracks consumer services companies selected from the S&P 500 index.

Standard & Poor’s MidCap 400 SPDRs (MDY:AMEX)

Tracks the S & P MidCap 400 index, which measures the performance of the mid-size company segment of the U.S. market and complements the S&P 500 seamlessly.

iShares Russell 2000 (IWM:AMEX)

Tracks the Russell 2000 index, a popular benchmark for mid- and small-cap companies. The Russell 2000 Index represents the second tier of U.S. equities, or companies with market values between $20 million and $300 million, which account for approximately 8 to 9 percent of the total market. Russell’s methodology leads to relatively high turnover.

iShares MSCI EAFE (EFA:AMEX)

The iShares MSCI EAFE Index Fund tracks the MSCI EAFE Index, the top non-US large capitalization index that includes all major economies (except US) and no emerging markets. A popular way to gain foreign exposure.

Standard & Poor’s 500 Index Depository Receipts (SPY:AMEX)

The first and still the biggest ETF, this inexpensive fund (pronounced Spiders) tracks the S & P 500 index, which is widely regarded as the standard for measuring large-capitalization U.S. stock market performance. Some selectivity by Standard & Poor’s surrounds an otherwise methodical list of the 500 largest traded firms.

Nasdaq-100 Index Tracking Stock (QQQ:AMEX)

Tracks the Nasdaq-100 index, which includes 100 of the largest companies listed on The Nasdaq Stock Market based on market capitalization. It is widely perceived as a technology benchmark and includes computer hardware and software, telecommunications, retail/wholesale trade and biotechnology. It does not contain financial companies or investment companies.

The three biggest exchange-traded funds as of Feb. 29, 2008, were the $66 billion S&P 500 SPDR, managed by State Street, the $46 billion iShares MSCI EAFE and the $26 billion iShares MSCI EM, both managed by Barclays, according to data compiled by State Street.