egScanner is an ip scanner which scans ip lists for specific ports. egScanner is multi threaded and on my computer can scan more than 50 hosts/sec if using 30 threads and scanning for one port. egScanner is written in java and source code is included.
You can download it from the following link: https://packetstormsecurity.com/files/download/26519/egScanner.tar.gz
Source: https://packetstormsecurity.com/files/26519/egScanner.tar.gz.html