Things have been rough for this galaxy. There are stellar streams strewn all about, the dust disk is warped all over the place, and there's hardly any star formation going on. That's what makes it so cool, though. I love the way the dust disk is pushed and pulled around, but still maintains semblance to a disk.

BONUS: If you look down at the bottom, next to the two red stars, there's the cutest little hourglass nebula I've ever seen. I think it's a planetary nebula, anyway. It's either a planetary nebula that's fairly typical, or the weirdest galaxy I've ever seen. I'll defer to Occam's razor for this one.

Edit: Some Galaxy Zoo people and Phil Plait are shooting holes in my idea that it's anything but a galaxy. Apparently there ARE galaxies that look exactly like this, such as NGC 2665. I'm just gonna redact that whole paragraph for now.

Color from SDSS again. Data for that may be found here: dr12.sdss.org/fields/name?name=arp156

NASA/ESA/SDSS/Judy Schmidt

Establishing HST's Low Redshift Archive of Interacting Systems

Luminosity: ACS/WFC F606W Red: SDSS i Green: SDSS r Blue: SDSS g