"Here's a kind of an application that is sorely missing from a stock Gnome installation and not many Gnome users know about: Gnome-PPP, a front-end to the wvDial, a modem/ISDN dial-up software. Read more for some quick info on the app and a screenshot.
"Version 0.2.1 was released just yesterday. To get a working copy of Gnome-ppp, you will need a modem, the pppd daemon and the wvDial software (stock Slackware has a problem with wvDial, but fortunately a patched package is available)..."