Meet Coin (YC W13), a startup creating a universal credit card 13 years ago
Based on Coin's FAQ:
1. Yes, it should be usable with ATMs without issue.
2. You cannot lock your coin with a password, but it will deactivate after it loses contact with a phone after a user-specified amount of time. In theory, I'd assume you can disable Bluetooth on your iPhone and it will effectively "lock" your Coin until it can pair with your device again.