Call restaurant:
When you look out your window, you can see the phone number of a restaurant. 
You can use the phone to call that number for fun.

Unlock Chainsaw 
Beat the game once, save and load the new data. Then, in the Forest World, near 
the car, search for a cut trunk, the Chainsaw is right beside it. 

Unlock Eileen's Nurse Costume 
Complete the game on any skill level and then restart using the same save. 
Check room 302 for the costume. It can be selected on the 3rd run through.