Angry IP Scanner - (Freeware) Very fast IP scanner for Windows. It can scan IPs in any range, even 1.1.1.1 to 255.255.255.255. Its binary file size is very small compared to other IP scanners.
wGateScan - (Freeware) Famous scanner to find Wingate servers on a class C or B network and help you to spood da world :). wGateScan v4.0 allows you to scan a range of hosts - ex. : 194.128.aaa.bbb to 194.128.ccc.ddd You can now connect the IP you've found to mIRC and SOCKS4&5 proxy are supported.
Socks Scanner - (Freeware) Searches public socks server.
Send-Safe Proxy Scanner - (Shareware) Program designed for searching for HTTPS/SOCKS proxies over the net by scanning IP ranges and checking existing lists of proxies.
SuperScan - (Freeware) A powerful connect-based TCP port scanner, pinger and hostname resolver. Multithreaded and asynchronous techniques make this program extremely fast and versatile.
Proxy Grabber - (Shareware) This program can help you scan any range of addresses on present SOCKS Proxy and copy the found addresses services in a log file. Proxy Grabber does not use multi-threaded scanning. It allows you to simultaneously check an unlimited quantity of addresses on a SOCKS Proxy.
GeoWhere - (Shareware 16-day trial) It finds and let you test proxy servers for you to surf anonymously and speed up your surfing. The interface supports 10 foreign languages transparently.
ProXYZ - (Shareware) ProXYZ is a utility used to search for and verify proxy servers. Searching for proxy servers can be done in two modes: IP range scanning and Web Search. Retrieves proxy IP addresses and/or host names along with corresponding port numbers from web pages. Fast content processing algorithm capable to retrieve proxies from any text or HTML file.
Proxy Hunter - This proxy site port scanner will scan any IP range that you enter and search for open proxy ports. It lets you know if they are open and useable and also give you a rough speed indication.