Ok, this is now thoroughly tested and officially a very good guide for people visiting Athens for 3-4 days and staying in the center (e.g., A for Athens). I originally prepared this for my friend Sasha, but turned out to be useful to a whole bunch of people!
so you know that linkedin was hacked and millions of passwords exposed. If you use your linkedin username-password combination anywhere else, go and change it everywhere.
leakedin.org provides you with the info on whether your password was exposed (you type in your password and it checks – does not require username), BUT, do not trust leakedin.org or anyone who tells you that your password was not obtained by hackers. We only know that these people posted ~6millions of passes but you have to assume that they have all of them.
a good long term solution that is free and highly recommended is lastpass.com. Their add-on works great in all browsers and mobiles, is free, and anytime one of your passes is exposed you only change that one pass.
by the way, what kind of tech-savvy firm keeps the password hashes unsalted in the webserver? Seriously?