Stop for a moment and have a good, long think. When was the last time you read something vitally important in an email message?

Computer scientist Don Knuth realised that none of his incoming mail was any use back in 1990, and gave up using it there and then, having been one of email’s earliest users from the mid-1970s.

The chances are that even if, like the rest of us, you are buried beneath spam, there are still things you can do to mitigate it that don’t involve this drastic step of abandoning email altogether.

The most obvious is to ensure you use some kind of anti-spam filter on your email account. Spam filters are computer programmes that monitor the incoming messages and check them over, trying to second-guess whether they are spam or not.

These days, some of them are very good at it.

Most of them work by siphoning suspected spams into a different folder, away from your inbox. The downside is that this still requires you to check the spam folder for so-called "false positives" – messages that are not spam, but that the software has mistakenly filed away as such.

This means you still have to browse through a list of suspected spam messages, but to be honest, false positives are rare. Much more common is spam that gets through the filters and still makes it to your inbox.

It does this by including random snippets of text culled from ordinary, innocent websites. The idea is that the snippet of plain English will fool the spam filter into thinking the message is legitimate, and sometimes it works. Nothing’s perfect.

The golden rule of dealing with spam is that you never, ever reply to it. Doing so only confirms to the spammer that you are real, and you’ll get even more messages as a result.

Recently, though, I broke this rule on receiving a spam from an identifiable source, a company that clearly and openly identified itself in the message. Having confirmed on the web that the company existed, I contacted them (via a separate, throw-away webmail account), asking if they realised what they were doing.

The response was not encouraging. One of the company’s minions did reply, saying the message was "marketing material", therefore not spam, and offering to remove my name from their list.

Too late, I replied. No amount of claiming a message was "marketing material" takes away the fact that it was not asked for, and was sent without my request or permission. That makes it spam.

This brief email conversation was probably fruitless, but I made the effort because this seemed to be a genuine business trying to find its way on the web, and doomed to failure because its bosses simply didn’t understand that sending spam was only ever going to do them more harm than good.

If you’re in business and think that sending unsolicited email is going to help boost your profits, think again. A mailshot might indeed make a short-term difference and bring in a handful of new customers, but it will also anger and annoy many more. In the long term, it’s a mistake.

* Giles Turnbull has a website at www.gilest.org