In the last trading session, U.S. stocks were mixed as speculation of a Fed rate hike by this year-end was compensated somewhat by some strong earnings released recently. Among the top ETFs, investors saw (SPY Quick QuoteSPY - Free Report) gain about 0.05%, (DIA Quick QuoteDIA - Free Report) shed about 0.07%and QQQ  retreat about 0.4% on the day.

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

: Volume 6.93 times average

This U.S. media ETF was in focus on Friday as roughly 114,000 shares moved hands compared with an average of roughly 16,450 shares. PBS gained about 0.8% on the day.

The news that the telecom biggie AT&T will acquire the media behemoth Time Warner in a $85.4-billion deal, boosted the Time Warner stock and this media ETF. In the last one-month period, PBS was down over 1%.

(ERUS Quick QuoteERUS - Free Report) : Volume 4.11 times average

This Russia ETF was under the microscope on Friday as nearly 1.68 million shares moved hands. This compares to an average trading volume of 409,650 shares and came as ERUS lost about 0.07% in the session.

The fund has about half of its exposure in the energy sector. And with all the informal discussion going on about the possibility of an oil output cut among the major oil producers, this Russia ETF was probably on radar. In the last one-month period, ERUS was down over 0.5%.

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