no flash, and a steady hand is how i get my most interesting results...
or flash + a slower shutter speed ("night" mode on cheaper cameras usually gives you the same effect):
dunno, a couple stiff drinks to calm the nerves works wonders for me in avoiding the jitters when shooting without a flash.
take a deep breath, release all your air, then *gently* click the shutter. all of the above were shot with a nikon coolpix 5700 in RAW mode. imagine what i could do with a REAL camera!