COM Port Stress Test is a tool for testing a COM or RS232 port (device).
It is also a very handy utility during your LPT port development activities.
Simple Port Tester is a neat application created to test TCP and UDP ports.
Active Ports monitors all open TCP and UDP ports on a local computer.
Local Temperature LLC
It displays the current temperature for your area in your desktop tray.
VSPE is intended for engineers and developers to create/debug/test applications.
Famatech International Corp.
Retrieves versions of programs running on the detected ports.
UDP Test Tool is both a UDP packet generator and listening application.
Flachmann & Heggelbacher
Establishes TCP connections, accepts a TCP connection on a local port, etc.
The dialer uses one local UDP port and one local TCP port.
Meddler is an HTTP Server running on port 8088 on your local PC.
Tucson Software Services
Port Forward is Windows Service which forwards any arbitrary set of local ports.
FakeDaemon is a port listener, to trick and log attackers on your local system.
It is an advanced serial port test, simulation and data analysis tool.
PFPortChecker is a useful and reliable port test application.
Posiflex Technology Inc.
Set port settings and design print test for various Posiflex POS printers.
WampServer is a local PHP server that allows you to test projects.