Or, just keep a reasonably secure OS install and use that. I generally only use my laptop for personal stuff (banking, shopping, etc.) and screw around with anything "risky" in a vmware environment.

I change my passwords often and even change the credit cards I use online often. (I cancel the card and order a new one for $5. I tell them the card is damaged or I want to ensure it's not in many databases on the net.) You can even use "one time credit cards" if your provider supports it.

I know its more difficult today to keep your private info off the web. However, it is possible.