Eagle-eyed Reddit user and Harry Potter addict, iShootWithACamera, has noticed some similarities in the crappy gifts with the Deathly Hallows themselves though and how they actually represent the Hallows and foreshadow their importance. The fifty-pence piece is the Resurrection Stone, the toothpick is the Elder Wand, and the tissue is the Invisibility Cloak.
We know it sounds kinda out there coz the Dursleys couldn't have known about the three important objects, let alone that Hazza would need them to defeat Lord Voldy. But they're the ONLY gifts from them that are mentioned in the books so it's a pretty big coincidence right?! Also nobody is wasting postage on a tissue unless it's supposed to mean something!
In another interesting twist, in The Prisoner of Azkaban book we learn that Aunt Marge sent Harry an insulting box of dog biscuits for Christmas which ended up being a big bucket of foreshadowing for Sirius/Padfoot appearing in Harry's life! And we all know JK Rowling doesn't write ANYTHING by accident!
Well isn't that something?