A lot of furry things I do aren't even related to my own sona species. >.>'
I do tend to hiss at people. I've started doing it with friends and people who have no idea about my furriness. And they're always like, "did you just hiss at me?" And I'm like, ".....yes." And that's usually the end of that.
I also wag my non-existent tail when I get excited. Which pretty much translates to that full-body wiggling thing that dogs with stub tails do. People don't call me out on that one as much though.
I shiver/shake like cats and dogs. I don't even mean to... it just kinda happens. And people are always like, "what the heck? Are you okay??"
Also, when I get angry, I get very wildcat like. I bare my teeth and stalk and pace and glare and all that jazz. I also lose my ability to talk (cuz I'm just too mad to speak. My body language makes much more sense to me when I'm angry). I lower my head and growl if someone gets too close, or I'll stand over them and give them the best ferocious "keep away" look I can.
My mom and I argue a lot, and one night she made me angry enough to be like that. She barged into my room (my territory) and every time I tried to non-verbally tell her to leave, she'd just get closer instead. Finally she was right next to me. She reached out and I slunk back, lowered my head, and did my best not to allow my lips to curl back.
And then my mom loudly goes, "are you on DRUGS???"