The problem - before you all rush down to your local boozer or petrol station - is almost exclusively limited to the US, where it seems that almost anyone can install a private ATM in their shop or club.
There was a rash of reports a couple of years back - and even a YouTube video - about scamsters reprogramming private ATMs to swap the $10 and $20 cartridges in the machines, and then drawing out their cash in $10 blobs, but in reality walking off with $20 bills.
Now I read that, despite widely-publicised frauds like this, ATM owners in the US are still not changing their default PINs.
And just to make life interesting, it seems you can now download private ATM manuals from some places on the Internet - if you know where to look (fx: ahem -Ed).
One news report quotes an ATM owner in Pennsylvania as saying he didn't know the default PIN on his machine was `123456.'
Cripes, if I ran an ATM in my shop, I think I'd make it my job to get to grips with the technical manual...