A holiday-shortened week is now in the books and despite a nice start to the week on Tuesday, a barage of disappointing economic data has sent U.S. stocks to another weekly loss. As of this writing the, S&P has careened 43 points from Tuesday's close and the Dow Jones Industrial Average has given back nearly 400 points. They say bad things in come in three and the last three days have been ugly to say the least. From the long side, finding opportunities that work in the ETF universe has become a taxing endeavor in recent days as even the defensive trade has become crowded, sending formerly dependable consumer staples ETFs lower. With sour economic data now the order of the day in the U.S. and headline risk still a problem in Europe, next week could make for some interesting trading, even if June gloom is setting in. With that, let's look at some ETFs to watch in the week ahead. 1) Market Vectors Rare Earths/Strategic Metals ETF (NYSE:

): Really, nothing has changed regarding the fundamental side of the rare earths story. If anything, it is gaining some steam as prices and demand remain high. Plus, politicians on both sides of the aisle here in the U.S. are starting to acknowledge the dangers in depending on China for rare earths supplies. Dips in REMX could be buying opportunities for the savvy crowd out there. 2) PowerShares QQQ (Nasdaq:

): With Apple's (Nasdaq:

) developer's conference kicking off on Monday and Steve Jobs expected to make an appearance, the iPad maker could breath some much needed life into the Nasdaq. 3) ProShares UltraShort Financials (NYSE:

): The premise behind trading SKF these days is so simple, it's borderline humorous. Does anyone want to be long bank stocks in this environment? Bueller? Bueller? 4) ProShares UltraShort Oil & Gas (NYSE:

): This is another case of fundamentals for the sector not changing much. Oil itself is volatile. We all know that. Oil stocks have been market leaders this year. We all know that, too. Oil prices may be lower than where they were a couple of weeks ago, but they're still higher than where they were a year ago so that means oil companies are making more money. Still, there is almost no way the likes of Chevron (NYSE:

) and Exxon Mobil (NYSE:

) are going to be moving higher while the Dow and S&P 500 are plunging. Given the weights of those two stocks in those two indexes, they'll be among the names dragging the market lower. For now, DUG works because the path of least resistance for the broader market is lower. 5) iShares MSCI Peru All Capped Index Fund (NYSE:

): Peru's presidential election is Sunday and to say this is a big deal for EPU's near-term fortunes is an understatement. The ETF moves higher almost every time it looks like Keiko Fujimori is going to win. When sort of reformed leftist Ollanta Humala leads the polls, EPU falls. Yep, it's really that simple.