I'll admit to having tried to roar like a lion or tiger ^^' Ears or tail? Not so much, though sometimes in my 'waking-dream' state...
A second 'I r not humen lul imma speerit wulf!!'/'Me so unique!! 8D' thread right after the first one was necro'd? ok
What a mysterious coincidence!!!
Anyway, back on topic...I don't do the whole "flatten my imaginary cat ears" thing, but when I yawn, I sometimes like to pretend that I have the jaws and teeth of a mandrill.
(http://farm8.staticflickr.com/7224/7265597364_cc09a0abbd_z.jpg)
Mandrills make the werewolves from Van Helsing look like gummy toothless babies.