external Images unrelated to emails

My company logo appears in web based mail.

[johnnynation]

Hi everyone,
I use my work computer to access my gmail account. The images in the emails are blocked most of the time. But in one email I opened, the images from that particular sender/site were blocked, but the logo of the comapny I work for was there instead.
Do these images automatically attach going through the firewall or servers, or is Big Brother watching me?
Thanks all!

[mattcg]

I guess your network administrator must have installed some ad-blocking software on the server to reduce traffic. When you try and load an image from a known advertising host, it will replace it with the logo.