In response to [Sklivvz request][1], we can update the 404, Error, and captcha images as part of site update, but I could use some help brainstorming images that better represent the community. Please post suggestions as answers below.

NOTE: In order to not delay the launch of the new design, we may retroactively change these after the new design goes live.

Here are the current images: 

* bigfoot (404)

 ![bigfoot](http://skeptics.stackexchange.com/content/skeptics/img/404.png)

* weird Darwin thing (captcha)

 ![darwinoid](http://skeptics.stackexchange.com/content/skeptics/img/captcha.png)

* ufo (error)

 ![ufo](http://skeptics.stackexchange.com/content/skeptics/img/error.png)


  [1]: https://skeptics.meta.stackexchange.com/a/3377/26048