i use a burr grinder, temperature controlled kettle, weigh the beans and the water, and use a pour-over method with a decent paper filter.

but in my experience, freshness is the biggest factor to good coffee--mainly being freshly (and adequately) roasted, but also freshly ground before use. everything else seems to be relatively marginal after that.

edit: i buy locally roasted coffee that's delivered to my door for about the price of starbucks or peets ( <=$1/oz ). that's been the biggest difference.