[url=http://www.playauditorium.com/]Auditorium[/url] is a very nice relaxing Flash-based puzzle game. If you need something “for in-between”, this is one for you.
[quote]Auditorium is about the process of discovery and play. There are no right or wrong answers; there are many ways to solve every puzzle.[/quote]
A related note: I have preordered [url=http://www.crayonphysics.com/]Crayon Physics Deluxe[/url] a while ago! If you like games based on “real” physics, check it out (there’s a free flash clone called [url=http://magic.pen.fizzlebot.com/magic-pen.swf]Magic Pen[/url]).
Update Jan 9th: Crayon Physics Deluxe has been released!