Look! My Spine!
Bhuahaha (a practical joke)
I taped this to the outside of my sister's window... she said she's gonna clean the blinds. I'm waiting for the scream any moment now... bhuahaha
A large realistic fake spider might work better?
My late grandfather had a bear skin rug that he donned many years ago (back in the 50's) to go "scare a neighbor". It worked, but my grandpa almost got shot!!!
I stuck a huge plastic cockroach to our shower wall once. Right behind the shower curtain. My sister went to take a shower, and about 5 minutes later she yells down, "MOM! MOM! CAN YOU COME UP HERE! FAST! SOMETHING'S IN THE SHOWER!"