I love Kongregate. As a husband and dad, my days of having several uninterpreted hours to play games are long gone. They have hundreds (thousands?) of casual games you can play for a few minutes at a time.
I've been playing there for years, and have amassed enough points to be level 35 or so (for whatever good that does).
There are only two hard things in computer science: cache invalidation, naming things, and off-by-one errors