Apparently someone just took some action, because now the NYSEARCA:AGQ = "ProShares Ultra Silver" is no longer available on Finance, even under a wrong name!
The ticker symbol now went back to defaulting to LON:AGQ, which is the Arian Silver Corp described by Darren below.
If I force Google Finance to show me "NYSEARCA:AGQ" by putting the full name into the search box, one eventually gets the correct market price, but now under a different wrong name: "ProShares UltraShort MSCI Japan (ETF)"
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