Teaches me more about hardware than formal education, reasons being:
a) Overclockers are the kind of people who when told not to press the big red button will examin the button, try stroking it a bit maybe, and then ever so gently pushing it one iota at a time untill it blows them up. Thus you learn the true limits and effects of tech rather than just what's written in the manual.
b) It's fun - so you can be arsed to read this techy stuff. Who CARES about weather RAM gives you 5% performance boost max between value and pro stuff. Except if you know the effect this has on overclocking, the effect of deviders, etc. etc. then you can get your machine to go faster - and that's a tangable gain you built yourself giving you a sense of achievement.
Oh, and of course it is something for nothing in my case as I'm a cheep skate - still on Pentium D my friends, who needs more than 3.5 billion calculations a second? Not me.
Find I learn LOADS more by doing rather than someone sitting in front of me and telling me the theory etc