So I have NO CLUE how to put this back together. I don't even remember what it looks like or what it's even called. I took it apart 3 years ago and it's still driving me crazy. Anyone have any ideas?!?!?!
I believe it is the Squarrel puzzle, invented by Ronald Kint-Bruynseels. You can find a description at Ishino's website, http://puzzlewillbeplayed.com/6BoardBurr/Squarrel/. It looks like there's a solution video at https://youtu.be/GxMKdVrhxow. There is also Andreas Rover's excellent BurrTools software that can solve puzzles like this if there are no rotational movements.