if you do crunches in correct form you should really hurt after no more than 15 reps (i like to add a 5kg weight tucked under my chin which gives a nice burn)
here is a crunch done in correct form
http://www.exrx.net/WeightExercises...s/WtCrunch.html
working your abs will give you a six pack but only getting your body fat below 8% will reveal them. you cant just target certain fatty areas either. eat good and exercise properly and you will get what you want.
on a side note, why is it that people feel the need to give information about something they obviously know nothing about?
doesnt affect me because i can see though the bull**** (like many before me, i took the time to learn how to exercise properly).
When i see dudes like MVP¤¥¤JI€GALO spitting misinformation about something as potentialy dangerous as exercising it pisses me off
anyway ive had my rant, im off to take some valium..