Here’s a silly little blast from the past I felt like sharing. Enjoy :-) (See also this update.)
First, a little background: 
Back when I worked for Microsoft, there was often something new and curious coming along. Force-feedback joysticks, for instance. But they also had some really mind-blowing tech partnerships, like the Timex Data Link watch that was released in 1994 – that’s nearly twenty years ago!
This watch was, on the face of it (hah!), a normal digital wristwatch, but it had a special feature: a lens! Today most people would think it’s a webcam (in a watch?!) but it was in fact a wireless download “eye”. This worked in conjunction with MS Outlook and special Data Link software. The trick was that the watch could download calendar and contact data from the computer, and the way it did this was that the computer screen turned all black except for a series of flashing white bars that the watch would recognize and “read”:
This was amazing technology in the nineties, folks!
I had a few of these watches, and the very first model came with a plastic wristband that was decorated with an interesting pattern of zeros and ones. (Click the image for a larger view.) During a particularly boring university lecture, I noticed that there were exactly eight digits per line. As we all know, eight ones or zeros are eight bits of data, and eight bits are one byte. A byte is usually represented by a single character … so maybe there’s a message here?!
Warning: nerd alert follows.
I grabbed a pencil and copied the digits onto paper, then calculated the integer values so that I could then map them against an ASCII table to get the characters they represent – in the end, to reveal the secret message!
Do you know the ASCII table by heart? Neither do I. I wracked my mind trying to figure out where the alphabet starts. (Hint: 01000001 equals 65 equals “A” in ASCII.) Finally there was a brief recess and I ran to look it up. I could now decode the bytes into this text:
LISTEN TO THE LIGHT
Get it? It’s got an eye and it looks for barcodes and it reads by the light on your screen! (This victory was an intense moment for me back then.) The code even included those spaces. Whatever geek had planted this was being exact.
Having decoded a secret message, I thought I was really clever. But more was to come. You see, a wristband has two parts and there were more digits on the second half (the one facing away from me while wearing the watch; on the pinky side, so to speak). But frustratingly, these digits weren’t full rows anymore. They had gaps and trailed into nothingness. Surely, this was not part of the riddle?
The first three rows were complete and read “IF ” but then it was incomplete. I tried various tricks but nothing made any sense. What’s a man to do? Remember, this was 1994 so I couldn’t just Google it or ask Superuser.com or Reddit or some such common source of wisdom we have today. So I wrote to a newspaper.
The Danish newspaper Ingeniøren is a weekly publication by an engineers’ labor union, and it always had some weird and fun story on the last page. It was an excellent place to ask for help!
Amazingly, the paper printed my open letter, along with a photo of the watch, and I waited in great anticipation for reader responses to be published the following week. And there, finally, was the solution. It was tricky indeed and I am very sorry that I didn’t save the newspaper (I’ve moved about ten times since then!) and I can’t find it online (remember: 1994). But the essence is that the bits were intentionally incomplete because they weren’t ASCII but rather old-skool mainframe codes or even assembler instructions. One part was translated into “U”, then another was a “cancel” instruction that was commonly written as “CAN”, and finally, a clear command, in shorthand: “C”. So I ended up with this complete secret message:
LISTEN TO THE LIGHT
IF YOU CAN SEE
And that is the coolest watch I ever had, and I was very proud to have found and decoded a message, even with help from newspaper readers.
Thanks for endulging me – all of the above is written as I recall it without research; I’ve only grabbed the images from Wikipedia.