A few weeks ago we mentioned that the headers of JPEG images created by Adobe's Photoshop image editor contain three tags - JFIF, Adobe and Ducky - indicating the file is in JPEG File Interchange Format and produced by an Adobe program called Ducky.

We asked if anyone knew why Ducky should be the program's ID. Reader Bill Verzal suggested we go to a certain page on Adobe's Web site for some details.

This page tells us the reason for this eccentricity is that developers have a rubber ducky obsession. If you have Photoshop, check out the page and try the Easter eggs - it is obvious that those coders were clinically obsessed.

Un petit divertissement (as the French would have it) - Bill's signature reads: "There are only 10 types of people in the world: Those who understand binary, and those who don't . . ."

After our recent discussion about DidTheyReadIt, Jim Michael wrote: "As an e-mail administrator for a midsize government organization, a service like DidTheyReadIt.com is not a welcome idea. At first I thought of several ways of preventing our proxy server from allowing access to didtheyreadit.com (all browsers here must go through a proxy to reach the Web, and thus the HTML messages while being rendered are also subject to the proxy's rules), but I could see some holes in that approach. Then a colleague said 'why not simply put didtheyreadit.com in your DNS, pointing at a bogus address?' Brilliant! If the image can't be resolved to the server holding it, tracking doesn't work and life is good again."

Chris Miller came up with a similar solution: "I went about gathering the information on DidTheyReadIt through SMTP tracking (and mail body properties) instead of capturing it through Winsock. As one of Lotus' largest application service providers, DidTheyReadIt is a concern because this type of tracking is not acceptable. As you know, with Notes you can work offline and not have the perweb.nsf database pull the image file, but this was still not acceptable. So we stopped connections from rampellsoft.com servers entirely through reverse DNS look-ups and blocklists. It has worked well so far. I consider you knowing when I read my e-mail just like finding out when I got your voice mail and how many times I listened to it. I can see the conversation now, 'Yes, Mom, yes, I did get it. Yes, I listened to it twice for 48 seconds.'"