I needed a custom pulser / throbber animation for a software project (Similar to the kind you see in Ajax loaders) and given my propensity for programming versus art, I wrote a somewhat daft, simple application to dump out the aforementioned animation.
If you fancy using this in your project, be my guest.
I’ve already used PNGOut to optimize the image’s size. Bringing it down from 16KB to 11KB.
On a point of interest, the file size for a skyscraper (tall) version of the above image, even after optimization, was 16KB, 5KB larger than the wide version, which illustrates the extra capacity needed to deal with those extra rows and most importantly, the loss of optimization potential.
Here is an animated GIF version (8KB):
There are also other services that deal with this kind of thing for those interested (amongst others):
Have a great day.