"For example." It's a favorite phrase of the various Polish devs I've known, for some reason.
I like it! It looks fun and a little mischievous. I hope someday we start using fx in the same places we use ie or eg.
EDIT: My beautiful Finnish wife informs me t.ex. is also used in Swedish in a very similar way, till exempel or something like that. So maybe it's a Northern European thing too?
I believe it's something along the lines of "flagrant excision" (of established language conventions).
The resultant confusion from such communication innovations may be justifiable in service to a larger goal, e.g. making a clean cultural break from ancient lion-torturing Latin speakers.
Be the change you want to see. Et cetera, et alii.