I knew I forgot something right before the new design launch today. I didn't get a chance to create custom images for the 404/Captcha/error pages on the TeX site.

Do you have any suggestions?

A few examples from other sites:

Cooking site's 404:

alt text

Gaming site's CAPTCHA

alt text

Photography site's 404 (Normally for Captcha, we do a "robot" theme.)

alt text

The idea is to have these images somewhat light hearted, and reflect the theme of the site. What are your suggestions for this site?


For a 404, there could be a play on some of most common TeX error messages. I think the Undefined control sequence is most appropriate.

As for an image, something simple like this:

\404{Page not found}

! Undefined control sequence.
l.6 \404

Or some variation thereof.

Probably rendered in different styles, to distinguish user input from TeX complaints.

  • 3
    But the standard catcodes of 4 and 0 won't allow that to happen. I think \cdiv would be more more in the spirit of TeX. On the other hand, how many would recognize what it stands for? Perhaps it would be a great inside joke. Oh, what the heck; I'll enter it as an answer so people can vote on it. – Harald Hanche-Olsen Feb 11 '11 at 14:58

Badness 10000!!


alt text

We don't know how you arrived in room 404, but we have been working for a long time to correct all bugs!

  • 1
    I think this type of old book illustrations work really well! Here's a good site where all the images are in public domain: oldbookillustrations.com – Jin Nov 13 '10 at 4:23
  • @Jin Thanks - and I love the new design! – Yiannis Lazarides Nov 13 '10 at 6:10

Use one of Don Knuth's Road Signs or the Dangerous Bend Sign

Dangerous Bend


What's with something like this:

> \page=undefined.

Maybe in combination with an assign tracing:

{changing \error=0}
{into \error=404}

One possibility is this variant on Martin Tapankov's answer:

\cdiv{Page not found}

! Undefined control sequence.
l.6 \cdiv

Look here if this mystifies you.

  • 4
    Ha ha. I had to look at the URL (but not click through). – Loop Space Feb 11 '11 at 18:52

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