Very cool and creepy atmosphere! I really liked that the notes and new objects had a considerable time between them, it made me sit and stare at the hole with anticipation every time I put in the object and getting really excited whenever something new came out. The revelation for what the strange objects you had been collecting was used for was also quite cool!
One small problem I had when playing the web version was that the game did not capture my mouse again after tabbing to another application which meant I had to restart the game.