Sorry to hear about what happened to you.
My cards are set-up to disallow charges over a set amount, without a verbal confirmation from me (basically I have to call-in, answer some questions only I would know the answer to, and authorize the charge).
I also manage my card accounts closely, keeping in these accounts only about 20% more than I plan to use during a given period. I only move the money over from an account that I don't have a card for, as I need to.
I pay extra in service charges by having multiple accounts at several banks, but service charges are tax deductible, and it substantially minimizes my exposure to scammers.
The same with PayPal. I only keep in there 10-20% more than I have a plan to spend, and then only move in new money as necessary.
Some good tips in this thread...
ADG