And if so, what does it do?
I've noticed it in some html written by a former co-worker (so I can't ask the author). I'd guess it was a typo, except that it's in a couple different places in a couple different templates, used as the source attribute for an image.
For example:
<IMG height="6" src="ihttp://www.ourdomain.com/images/f2f3f4.gif" width="5">
The top google results point to some sort of apache/php/mysql installer, but we're running IIS, so I can't imagine that that's related.