For people asking about Recettear, Chantelise, and Fortune Summoners:
All three are very different, with their title cluing into what they're about. All three are good though if the core mechanic looks good to you, as I can tell you all three execute their ideas very well and have a lot of charm and content, and each is pretty challenging.
Chantelise is a dungeon crawler where you have a focus on collecting gems for spells and combining them for stronger spells and executing them well. The combat is a more strategic hack'n'slash and requires strategy, with some pretty fun bosses.
Recettear has a focus on running an item shop and can be pretty addicting as you try to stock up, hire adventurers to raid dungeons (you control hired adventurers), barter, and more. Pretty fun and unique core mechanic.
Fortune Summoners is a platformer RPG that has a focus on summoning things to do various tasks for you and has more of a retro platformer feel to it with a fairly fun mechanic hook and RPG elements.
All three are worth your time if they look interesting to you, especially at this price.