Shawn's Shoebox: Check out the private letters Shawn has stashed in a shoebox underneath his bed ... and do it quickly before catches you:
http://www.usanetwork.com/series/psych/games/shoebox/
World of Psych: If these walls - and everything else on the set of Psych - could talk, here's what they would say (ability to channel the thoughts of inanimate objects not required):
http://www.usanetwork.com/series/psych/games/world/
