Harry:
You got him a bunch of lottery tickets and money.
Ron:
A handmade book of everything you like about him.
Fred:
A bunch of stuff from the muggle world that he was asking questions about.
George:
You left a bunch of cute notes around.
Draco:
A brand new case for his watches.
Neville:
A watch, a stereo, a new duffle bag, and cologne.
Marauder era
James:
You got him a bunch of 'Ruby Snap' cookies from the muggle world.
Remus:
A giant Hershey's Kiss
Sirius:
You also left a bunch of cute and loving notes around