All of these are either very good or at least interesting and definitely worth your while.
The ArtStyle series (Light Trax, Rotozoa, Cubello, Orbient, Rotohex), Tetris Party, all the BitTrip games, Harvest Moon Little Shop, Blaster Master Overdrive, both Final Fantasy Crystal Chronicles games, Castlevania The Adventure, Cave Story, Contra Rebirth, ExciteBike World Rally, FAST, Final Fantasy 4 The After Years, Fluidity, Jett Rocket, La Mulana, Let's Catch, LIT, The Magic Obelisk (this one isn't available anymore, sadly), Lost Winds 1 & 2, Maboshi's Arcade, Megaman 9 & 10, MotoHeroz, My Aquarium and My Planetarium are quite nice, NyxQuest, Pokemon Rumble, the Phoenix Wright games if you haven't played them elsewhere, Rage of the Gladiator is ugly but somewhat decent, Rubik's Puzzle Galaxy, ShadowPlay, Snowpack Park, Space Invaders Get Even, Star Soldier R, Gradius Rebirth, the Strong Bad games, the Tales of Monkey Island games, ThruSpace, Toki Tori, World of Goo, You Me and the Cubes. That's what I can remember right now.
I can guarantee you'll find a few games of interest in that list. Keep in mind that some names might be different in other regions, like Fluidity / Hydroventure.
If you have access to the Japanese shop, Line Attack Heroes is really nice and so is Pole's Big Adventure. The Pokemon Mystery Dungeon games are there as well.
Theres other stuff that might be worth a look at depending on your level of tolerance, like DrillSergeant Mindstrong (so bad it's good), Evasive Space, Eco Shooter Plant 530 (the only mediocre game Intelligent Systems has ever done), Driift Mania, to only mention a few.
That Lost in Shadow game, has anyone played it? Any good?
I haven't gotten around to finishing it but I can vouch for its quality, specially if you like interesting, different games. It's not perfect, but it's not bad at all. It's also one of the last Hudson games, so there's that.
Also, Trauma Team needs to be mentioned a few more times in this thread.