Tingle's Rosy Rupeeland.
Jokes and hating aside, the game seriously and honestly has a really -really- unique and fantastical atmosphere, unconventional but addicting gameplay hooks (that actually work great, too), insanely humorous characters and dialogue, interesting environments, and really neat music and sound effects.
For the kind of game it is, it's got great production values, and while playing through it and discovering all nooks and crannies, characters and secrets, you really get a great sense of all the dedication, effort and fun the devs poured into the creation of the game. I honestly couldn't wrap my head around how deep and engaging the whole affair actually turned out to be when I was playing it. I'd highly recommend it to anyone even remotely interested in adventure games.
Oh, this is a good 'un. I need to get this back from my Bruvver, since I had only played about half an hour of it before he swiped it from me. I liked what I saw during that time, and I have to love a game that made me crease up with laughter (Zelda's "open chest theme" played on a ghetto blaster was a highlight). It feels like a Paper Mario style game where the writers have more freedom to be cheeky.