I second birdastrompgman; I too use Droid Sheepguard.
I also *never* do any banking/credit card access/essentially anything having to do with money and related accounts on public wifi -- ever.
I check my gmail, my gReader Pro app, FB and twitter, and that typically can keep me busy for quite some time. I'll also do web searches and such.
Basically, just be smart when on public wifi.
On a side note: I live one house from the corner, and across that street is a park. There are cars parked along that park all the time, often late at night. About a year ago, the police busted a car with a couple in it, using a laptop and accessing an unsecured wireless network in the neighborhood. I'm guessing they stopped to check out why the people were sitting in their car and discovered said laptop and what they were doing. I don't know whose network they were accessing, but these people are out there, doing their nefarious deeds!