One of our clients that does interior design asked me to do a mailing list for them. Not a problem. We have done a lot of leg-work to make sure that we can code an email that gets past most spam filters out there (since this is both targeted and subscribed to, its not spam anyway – just automated).
Only problem was to get some way to track if people were actually reading the things, or even receiving them at all! Since read receipts are an iffy one since they are optional, we decided to do something server side to check it. As it is database driven the code can be altered for each email that gets sent out and therefore the simplest way is to include an image (such as the company logo) with the path altered to include the ID of the email address from the database.
Since there isn´t an image there on the server, Apache and htaccess will handle the 404 error and direct it to a PHP file. This will then take the ID from the requested URL and then update the database to say that email has been read. It will then stream the requested image out to the email client. Ah, Apache and .htaccess, if I could I would run away with you both and live on a mountain side in peace.
Not a bad idea though, time to see if it´ll actually work…
I'm a web developer based in the East Midlands, UK and if I keep up the current rate, I might have developed 3 million sites by the time I retire