Several things you'll see quite often on an achievement hunters list, quite a high number of low quality 5000G titles, a large number of puzzles and shooters from the mad lads over at East Asiasoft and most of Ratalaika's catalogue.
One other thing you'll find is a little known game series called Aery - Little Bird Adventures.

Produced by EpiXR Games, the Aery games take you on a journey through a dynamic polygon landscape through the views of a little bird as a narrator commentates on the deep philosophy that surrounds the area you explore while collecting stars.
On it's merit the narratives can come across as a little too real or a little preachy especially when the music is designed to provide a zen like aura to your gaming experience, the first few games certainly keep up that appearance, but as time went on, the games were getting worse and worse.
16 games + 1 spinoff that uses a paper plane later and the problems keep piling up.
Collectables out of sequence.
Slow framerate performance issues.
Constant crashing.
Corrupt graphics.
Achievements popping at the wrong time or not at all.
A skip option on PC that let's you gain achievements by skipping all the levels.
Reusing levels multiple times.
Vikings in every bloody game possible.
Collectables stuck behind impassable walls.
Having the same soundtrack in every game.
And the biggest one of all, forgetting to add all the levels!
This should've been problems solved in game one but they've taken the Ubisoft approach of not testing their games and wonder why there are so many problems, and it's getting worse with every game; what started as a simple bit of escapism in a zen like environment has turned into an example of gaming greed at it's most vile.
At time of writing, I've played six of them, I've no plans to play all 17 titles any time soon, only 15 of them are fully completeable as the two most recent ones are broken until patched.
To put that into perspective, assuming I make 500,000 lifetime gamerscore this year and I play all the titles, 3% of my score would just be Aery games.
D-Tier for all the games.
Trash Tier for just the developers, stop being bitches and hire a play tester for god sake!