You enter your mobile number, a PIN number will be sent via text to your phone, and you then enter the pin on the Web site to see confirmation of all donations you have made via that phone number.

FORBES: Charitable Giving

Offline cards do not require you to enter a PIN.

FORBES: Credit, Debit And Charge: Sizing Up The Cards In Your Wallet

After browsing a site and making your selections, you click the eWallet icon in your Windows task bar, enter your PIN number, and drag your plastic of choice onto the site's order form.

CNN: Don't forget your eWallet when you shop online

All that the user needs to do is swipe the card at the existing check-out machine and enter a four digit PIN.

FORBES: eBay Is Charged For $50 With PayPal's Discover Partnership

And again, remember that a joint return requires two signatures: if you are filing a joint tax return, you and your spouse will each need to create a PIN and enter these PINs as your electronic signatures.

FORBES: Taxes from A to Z: X Is For X-Mark (Signature)

The taxpayer and the preparer both have PIN numbers they enter into the record when they file.

FORBES: Don't Robo-Sign Tax Returns

Rather than visiting a kiosk to rent a bike, you'll be able to use a smartphone app to locate some available wheels, with position information broadcast by a built-in GPS. Once you find a bike you want to rent, the system will send an unlock code to your handset, which you'll enter into a handlebar-mounted PIN pad.

ENGADGET: NTT DoCoMo Shared Bicycle Initiative hands-on (video)

When you feel like snagging yourself a pair of fly kicks, all you'd need to do is enter your username and password, or phone number and PIN.

ENGADGET