whatPorts is a multi-threaded port scanner written in cocoa. This means you enter a computer's address, the port range you want to scan, and click the scan button. The scanner will cycle the ports on the host entered, and report back any ports that are open, attempting to match the port with it's registered port database to determine the service that is most likely running on that port. If the service can be determined, then it will inform you, otherwise, it will tell that it is unknown. Tests have shown that this scanner tends to run significantly faster than the scanner shipped with OS X, also, it goes one step beyond by telling you what service is most likely running on that port.
v. 1.1 - This version added a descriptive progress indicator, a port lookup database to determine the service running on a given port, and a tighter scanning algorythm. Also now allows any host to be scanned, not just the local host.