I am breaking all the diversification rules right now by keeping almost 90% of my money in AIG. I used to hold ARR or AGNC, but I have switched to AIG in Sept 2012.
Portfolio contents at 12/31/2013
AIG (92%) BAC(4%) BRK.B(2%), AGNC (2%) ARR(1.5%)
I have been trading equities for over 15 years on my own time. I am a long-term investor, but I focus on a lot of momentum and growth stocks. I work in Finance at Apple, so I can't complain. Life is good right now.