PayPal has created an iPhone application along with Bump Technologies that allows iPhone users to pay one another by using their cell number or by bumping phones together. (Unfortunately its name could be a little snappier than PayPal's Send Money and its counterpart, Collect Money.) The same app can be used to swap other information.
Bump Technologies provides the bumping/swapping information immediately, and one uses PayPal with a cell phone number and PIN. The application tools also allow people to split up checks or factor tip or tax. PayPal previously used a text-message service but it never seemed to catch on. Now PayPal is working on a merchant application so users can use their phone to pay for goods -- even with a bump. The new app is available in 18 different languages for use globally.