I finally broke down and implemented Spam-blocking at toms.net.
Currently I am using the DNS blacklist of SpamCop.NET, (which is free to use for now), along with various rules that require resolvable senders and such. Eventually I will probably switch from SpamCop.NET to MailAbuse.ORG, as SpamCop says they will start charging and MailAbuse says that hobbyists and individuals can use it for free after signing various forms. The upshot of this is that I am relying on someone else's list of 'spammers', and the possibility exists that they will make mistakes, and that some non-spam mail will be blocked. If that happens (you would get a failure message that references SpamCop or MailAbuse, so you will know), please let me know the specifics and I can put in some kind of exception handling. If a lot of spam gets through, I will probably also add something based on analysis of things like lots of upper-case, dollar signs, and headers that usually mean spam. For now, it is just based on known bad spammers and forgery indicators. So far, the only piece of spam I've seen get through is one piece of Chinese-language spam (Gawd how I hate spam that doesn't even use a western character set and/or isn't in English. Give me a break.) So I might also look at a tool that scans for >128 characters in places that indicate non-Western character sets. Let me know if something is blocked that shouldn't be (I guess, if you yourself can't send mail to toms.net, you can call me at 3013205786). -Tom
