I didn't personally create any of them, just fletched them together when they were added on the EVE University forum (Thanks Keld!)
More details and all of them posted in the additional info link. Figured somebody might get a kick out of them on here
To install: Grab the "PonySheet.png" from the attached zip and put that somewhere on your Xenforo install (OMG Rainbow is a separate gif, same treatment). I put the two at [xenforo root]/custom_images/smilies and then used "custom_images/smilies/PonySheet.png" on the Admin page to add new smilies. Then enable the "Sprite Mode" option and enter negative coordinates, each icon is aligned to a 30x30 grid, excepting Trollestia at the end who starts at -70. So Trixie for example is at -90,-150, sized 27x27. Easiest way to get the exact height + width to enter is to look at the individual PNGs in the zip, I also personally use the filenames as the replacement text. Original Gimp format is also in the zip in case it matters.
Enjoy! If somebody wants to see any additional ponicons added feel free to post an image / icon / link on here and maybe I'll add another row later