SpamBurner supports the POP3 e-mail protocol, will work through most types of proxies, and supports an unlimited number of e-mail accounts. It also works with Yahoo! Mail and other web-mail services that offer a POP3 capability. It can also clean up offline e-mail in Qualcomm Eudora and Microsoft Outlook e-mail programs.
SpamBurner also has a really powerful WHOIS-Lookup feature (we call it AutoWHOIS), which lets you do WHOIS lookups from any hostname OR IP address -- it also is able to auto-detect the appropriate WHOIS servers, and it is integrated with SpamBurner's message viewer -- you select the part of the message headers you want to do a WHOIS on, and right-click, then click WHOIS. AutoWHOIS also supports proxy servers.