I thought I'd share a little experience I just had.
While going over my financial information I noticed a $1.00 pending charge on my credit card. I thought at first it was a soft drink I purchased through a vending machine on campus, but then I remembered it would have cost me more than a buck. I checked the details and apparently it was for a Steam purchase made last Monday. I have a Steam account, but I couldn't recall buying anything there over the last three months and have no subscriptions (I'm a infrequent user at best and was busy most of that time anyhow). I checked my Steam account and sure enough no such charge had been made through my account.
My father's credit card was recently hacked and whoever had done it had started out by making small purchases to 'test the waters' before charging more. I'm pretty sure that's what's happening to me. They probably made the purchase through Steam knowing it couldn't be traced to a specific location and betting that because a lot of small transactions are made through Steam (especially with the recent sales), a single dollar amount would go unnoticed and thus be a good way to confirm the account is active, not actively monitored, and squeeze a bit of money out of me. I'm not sure where else the $1.00 charge could have come from (let me know if I missed something).
I had the account blocked and will be receiving a new card in the next week or so. Mild inconvenience, but it could have been much worse.
Moral of the story? Monitor your accounts carefully. You see anything suspect, check on it. Hacks like this are all too frequent and can happen anytime to anyone. Just one of the joys of living in the digital age.