Flow
 

I read this excellent article by Jim Ramsey which should be a must read for all the designers and developers. The article is based on designers point of view but that should not affect your choice.

Flow is an powerful physiological experience that helps the user engage with the application/content without boredom or anxiety distracting them.

Designing for flow by Jim Ramsey. :-)

I guess, no one likes my threads. :-(

No, but we love you. :-P Just kidding mate, I'm reading it as we 'speak'.

[edit]; I read the first paragraph and I printed it to read tomorrow while I'm on the bus to work. Thanks!