Good issue.I have looked into a few things since this MF Global fiasco.Even Comsec if you read the fine print at the bottom is not gauranteed by CBA.You would expect it to be the safest but I beleive the best option is to have cash for instance spread accross a couple of banks.If push comes to shove and your cash is in a cash account in say etrade /comsec or westpac will these be gauranteed by the bank?