Not in one sitting mind you, over all clocked hours.
I have been playing FF Tactics Advanced, and noticed my clock has me at 74 hours, and I haven't even beat half of the missions. It got me thinking that some handheld games in recent year have had some serious logevity. So what is the most you have clocked on one game or the other.
My all time maximuim is Pokemon Red and Blue. Between the 2 I clocked 345 hours (that was the entirity of 11th grade thou, just so you know).