Hi,
I saw your question on ZSL and it rang a bell. It is a short 2x ETF based on the price of silver. It is paired with AGQ, which is the long 2x version.
I have had very good luck with AGQ, because of the distrust of our fiat system, and when AGQ is in trouble (like when JPM is shorting it) I switch to ZSL.
I have made a load of $$$ on these and other precious metals, but be careful. they are both very volatile, and being 2x, they may bite you.
Good luck in 2011,
crater