Nmap can make quick of work of doing a ping sweep of your network:
[usr-1@srv-1 ~]$ nmap -sP 10.50.100.1-255 Starting nmap 3.70 ( http://www.insecure.org/nmap/ ) at 2005-06-13 15:50 PDT Host 10.50.100.1 appears to be up. Host 10.50.100.2 appears to be up. Host 10.50.100.22 appears to be up. Host mondo (10.50.100.72) appears to be up. Host 10.50.100.82 appears to be up. Nmap run completed -- 255 IP addresses (5 hosts up) scanned in 3.228 seconds |