In the last trading session, U.S. stocks ended lower due to massive sell-off in Internet and tech stocks. Among the top ETFs, investors saw SPY and (DIA - Free Report) lose 1.6%, and (QQQ - Free Report) move lower by 3.2% on the day.

Two more specialized ETFs are worth noting as both saw trading volume that was far outside of normal. In fact, both these funds experienced volume levels that were more than double their average for the most recent trading session. This could make these ETFs the ones to watch out for in the days ahead to see if this trend of extra-interest continues:

iShares MSCI ACWI Index ETF(ACWI - Free Report) : Volume 3.68 Times Average

This world ETF was under the microscope yesterday as 11.8 shares moved hands. This compares with an average trading day of roughly 3.4 million shares and came as ACWI shed 1.5% in the trading session.

The big move was largely the result of heightened volatility and uncertainty that can have a big impact on stocks like what we find in this ETF portfolio. ACWI has lost 2.2% over the past month and has a Zacks ETF Rank #3 (Hold) with a Low-risk outlook

WisdomTree US High Dividend Fund (DHS - Free Report) : Volume 3.51 Times Average

This dividend ETF was in the spotlight yesterday as around 57,000 shares moved hands compared with an average of 17,000 shares a day. We also saw some price movement as DHS added 0.4% in the last session.

The movement can largely be blamed on the rising appeal for dividend products, which offer safety in the form of payouts, while at the same time provide stability as mature companies are less volatile to large swings in stock prices. DHS has gained 0.4% in a month’s time and carries a Zacks ETF Rank #3 with a Medium risk outlook.