I've estimated a lower bound of current Satoshi's fortune. My estimation is that he owns more than 1M BTC, or 100M USD at current change.

It is impressive, isn't it?
That's a good reason to stay anonymous!

I've used the data from the blockchain in bootstrap.dat, so my estimation does not take into account the last 6 months.

I've assumed:

1. Satoshi mined almost alone from 1/3/2009 to 1/25/2010 (block 0 to block 36288). This assumption is based on the Total Network Strength
(Mhash/s) that was constant at 7 Mhash/s for this period of time. (check in https://spreadsheets.google.com/spreadsheet/pub?hl=en&key=0AmcTCtjBoRWUdHVRMHpqWUJValI1RlZiaEtCT1RrQmc&hl=en&gid=0)
If Satoshi mined alone the first 14 days, then he mined almost alone for the rest of the year.

2. I assume that boostrap.dat contains only the best chain (not orphan blocks)

3. I only take into account coinbase transactions.

4. I've assumed that if a coinbase output is spent, then none of the spent coins went back to Satoshi.

5. From the 1814400 BTC awarded, 1148800 BTC has never been spent (63%)

6. The BTC/USD exchange rate is 100 USB per BTC

If someone wants to check my computations, is welcomed because I used a special block chain parser made by myself.

Best regards, Sergio.