The way I did it was mine myself some a bit first, transfer the BTC directly into MGTox, sell it for USD, buy BTC back when the opportunity arose, and repeat. I'm up to $294 now using this method on MTGox, though I won't be buying for a while now that the price spiked
What makes you think you are anonymous?
The governments are going to access all the records and come after you for capital gains taxes you did not report and pay.
When ever you FX to any currency, you are now required to report to FinCEN or your exchanger must keep records of your identity.
If you are in a jurisdiction where this does not apply (Europe?), your tax man will be coming... don't worry...
The Proof-of-Work in Bitcoin favors large investors in terms of obtaining coins from mining. I have a better design that would let all regular users mine more coins (you need a terabyte hard disk only). But this is not implemented.
Bitcoin : The Digital Kill Switch
https://bitcointalk.org/index.php?topic=160612.0