Ultra long ETFs

Ultra long ETFs (2 times return of the underline security):

1. Ultra QQQQ: QLD
2. Ultra Dow: DDM
3. Ultra S&P500: SSO
4. Ultra MidCap: MVV
5. Ultra SmallCap: SAA
6. Ultra Russell600: UWM

Short ETFs

1. SDD. Ultra short S&P 600 small cap.
2. TWM. Ultra short Russell 2000.
3. SKK. Ultra short Russell 2000 growth.
4. SKF. Ultra short Financials.

International and sector ETFs

ETF provides a better, cheaper (fee is lower than mutual funds) and quick way to play sector trend, but there are too many ETFs to select from, and most of them without selection process, they just follow a index.

International ETFs:

1. FXI. China Large cap 25 companies.
2. PGJ. Power Shares China ETF. Contains all of FXI's holdings, plus lot of small companies.
3. EWA. Australia ETF. A good indirect play with currency and commodity as well, since Australia has lot of mining companies, and its currency may strengthen against dollar.
4. EWC. Canada ETF. Has many energy companies and mining companies.
5. EWT. Taiwan ETF. Has high tech companies.
6. EWJ. Japan ETF.
7. EPP. iShares MSCI Pacific ex-Japan. Has companies from Australia, Hong Kong, New Zealand, and Singapore.
8. EEM. Emerging market.
9. EWZ Brazil.
10. EWW. Mexico.
11. EWY. South Korea.
12. EWQ. France.
13. EWG. Germany.
14. EWH. Hong Kong.
15. EZA. South Africa.
16. EWD. Sweden.
17. EWU. UK.
18. JSC. Japan Small Cap.

Sectors:

1. OIH. Oil drilling and services companies.
2. XLE. Energy companies.
3. GDX. Gold and silver mining companies.
4. GLD. Gold.
5. SLV. Silver.
6. USO. Oil.
7. PHO. Water ETF, a long term play.
8. IBB. Bio-tech.
9. IYH. Health care.

Currency ETFs

There are several currency ETFs. Basically let you bet on them if they move up against Dollar. Or you short them to get the reverse. It's a simple and safe way to play currency.

1. FXE. Euro. This is the first one and with about 1B asset, the largest currency ETF. Yield is 3.28%.
2. FXY. Japan's Yen. Yield is 0%. That is, return is negative if Yen is flat against Dollar since you pay the 0.4% fees.
3. FXC. The Canada's dollar. Yield is 3.78%.
4. FXA. Australia's dollar. Yield is 5.73%.
5. FXB. British Pound. Yield is 4.95%.
6. FXM. Mexican Peso. Yield is 6.28%.
7. FXF. Swiss Franc. Yield is 1.25%.

Out of these 7, I like FXA and FXC, to bet on commodities to go higher, which will benefit these two countries currency. Another way to play them is to buy country's ETF, like EWA and EWC.

Long and short ETFs

Now you really can play short and long of the market as you like, up to tow times of leverage. ETF is a great tool to play market now, if you can predict the market trend correctly.

Long U.S. ETFs:

1. DIA (Dow)
2. SPY (S&P 500)
3. QQQQ (Nasdaq 100)
4. MDY (MidCap 400)

Ultra Long ETFs. (2x)

1. DDM (Ultra Dow)
2. SSO (Ultra S&P500)
3. QLD (Ultrad QQQQ)
4. MVV (Ultra MidCap 400)

Short U.S. ETFs:

1. DOG
2. SH
3. PSQ
4. MYY

Ultra short ETFs (2x):

1. DXD
2. SDS
3. QID
4. MZZ