This website is a collection with over 6500 GIF's
in 88x31 format. In the late 1990 and begin of the 2000's it was very common to use these pictures on your personal website.
Many were included in the website creation software
or the service your website was hosted on like GeoCities
It's advised to first download
the pictures to be sure you won't lose the pictures and create a dead link. There is some debate
on why this particular size was chosen.
You can also make your own picture collection
and check for duplicates