Some people play them because they're looking for a casual gaming experience to simply to pass the time.
The basic free web-based game will satisfy your casual gaming needs, but if you really want to step it up, you may want to check out the Deluxe download (4.7MB).
Big Fish Games: This big fish is in quite the big pond of free casual gaming websites.
One of the main appeals of Real Arcade is when you download one of their titles, you get a complete casual gaming solution.
Many analysts and pundits have indicated that the PSP Go may be a better competitor in the casual gaming market against devices like the iPod touch and Apple iPhone.