HiLed allows you to simulate the LEDs of an external modem on an internal one.

HiLed displays eight LEDs: the CTS, DCD, DSR, DTR, RI, RTS, RxD, and TxD. The LED indicator lights keep you informed about the status of your modem and its connection.

The program can run as a convenient icon in the System Tray area of the Windows taskbar.