I’ve often thought about this question.  Here’s a nice answer.  It was nice to see that Schwab does offer a guarantee, but who knows if they’d really cover my loss due to my account being hacked.

http://www.kiplinger.com/personalfinance/columns

I think that their non-technical business processes are key to protecting you against someone taking your money.  By sending notification to your registered address for any address changes and not allowing withdrawals for 10 days after an address change, it sure seems like they are minimizing the risk.  I wonder if they would allow electronic transfers.