Tim:-"would anyone else like to share what they think their utility function is?" Seem to have missed this question the first time around - and it looks like a good question. My timid answer is thus: To maximise the quality of (my) time. This is no trivial task and requires a balance between achieving things in the world, acquiring new information (thanks OB) and achieving new things in the world, peppered with a little bit of good biological feelings. Repeat.