I am breaking all the diversification rules right now by keeping almost 90% of my money in one stock. I used to hold ARR or AGNC, but I have since switched to AIG.
Portfolio contents at 5/29/2013:
AIG (88%), BAC(4%), AGNC (3%), BRK.B(2%), ARR(2%)
Invested $1M in May 2009, portfolio now $6.5M~.
Received $1M inheritance, bought high quality "Brand-like" U.S. Companies with a long term outlook. Learning to hedge portfolio by selling $SPY. Trade high risk/reward option setups in cash account.