InsaneJournal

ε EPSILON: A sack of coins for each person, each totaling 100 coins. (spreadsheet)
Γ GAMMA: A tiny bottle of Amortentia perfume/cologne. And a chocolate bar, because Gamma's Amortentia includes a lot of chocolate.
ο OMICRON: The screen outside their window will flip to show pictures of their loved ones. If they mentioned or requested someone in particular in their wishlist, that's who they'll see. If not, they'll get pictures of someone from their family or someone else important in their lives.
Π PI(E): Four jelly wallets.
τ TAU: A make-your-own-tattoo kit, with enough materials to make approximately 5 large tattoos per kit, or 10 medium sized, or 15-20 small, or some combination thereof. They won't fade or flake off over time and could therefore be permanent, but can be easily removed with a special sponge that is included in the packaging. The design is completely up to the person who makes it and does not require magic.
υ UPSILON: Candy canes. No, they don't actually do anything. Sometimes a candy cane is just a candy cane.
ζ ZETA: A miniature Quidditch player toy on a broom. Everyone will get a different player, roughly the height of your index finger. In the common room, they will find a miniature set of bludgers, quaffle and snitch. There are 14 people in Zeta, so that's enough for two teams! Coach your little players and pick your captains, it's Quidditch time.