"Weird noises and happy shrieking voices" ... a passion of mine! The Katamari soundtrack is fairly representative of current Japanese laptop pop. I'd recommend these (hopefully the original poster is still kicking around these parts):
PINE*am -
Pull the Rabbit Ears and
Playing Intense Neural Electronica
YMCK -
Family Music
Macdonald Duck Eclair -
Short Short and
The Genesis Songbook
EeL -
Little Prince
Plus-Tech Squeeze Box -
Fakevox
Hazel Nuts Chocolate -
Cute
Be warned, not everyone's cup of tea. Especially not in the morning.