It is common knowledge that Internet users who connect by dialing into
their isp, often get disconnected after a few hours.

Windows can be configured to reconnect automatically upon 
disconnection, but it usually does so only when an application tries to 
access the Internet.  Also, this feature in Windows will only redial 99 
times before giving up.

I needed a program that will keep redialing indefinitely until 
reconnected.

For this I downloaded a small 200K freeware from download.com called 
CiDial.  Before that, I tried DUNCE, but it didn't meet my expectation.

CiDial does not create or change any registry entries and 
does not create or change any files outside of the 
directory it is run from. Installing and running it will not 
change your Windows setup. CiDial is not an adware program.

You should turn off Window's auto connect feature, it will 
compete with CiDial. Open "Internet Options" in the 
Control Panel and check "Never dial a connection" on the 
"Connections" tab.