The upcoming Skype version 2.5, seen at the eBay Developer's Conference, apparently will let you send or request money to other users directly from the client software. Since eBay, Paypal, and Skype are all one big happy family, you'll be able to Paypal money easily while chatting with the person you're talking to. Camwhores: Paypal $3 for another 5 minutes of show?
If they integrate this with the WiFi Skype phones, you could possibly be able to send money to people wherever you have a WiFi connection. Then again, if you have a cellphone, you could use Paypal Mobile and do that right now.