To get the bees to leave you alone when trying to pick flowers for money, buy the yellow spray item next to the flower seeds at the market. Use it to get all the bees down at the same time.
The magazines and book stand at the plaza where you will be sent to activate your account has two magazines. One will explain how to pick a lock. The other mentions your suspect's code names, but you will need the German dictionary to read it, as well as the post cards your roommate has laying around.
Create a gelato scoop of red, white, and green (in order) to get an Italian flag.
Go to the door to the left of Colin. Pick the lock using the hairpin from your closet to get an egg. At the end of the game, you will get some extras. To get all of the extras, find both easter eggs.
Repeatedly use the bathroom in Helena's and Nancy's bedroom to hear hidden dialog.
Go to the marketplace and go to the gelatin stand. Get the flavors cherry, coconut, and lime (red, white, and green; the colors of the Italian flag) to get an easter egg. At the end of the game, you will get some extras. To get all of the extras, get both of the easter eggs.