I did the dishonourable thing and looked it up. (Damn you Youtube!)

Apparently there are 3 endings (but only 2 videos). I've seen the best ending but I don't think I can muster the willpower to actually kill off the Little Sisters having discovered the plot. For the really bad ending, you have to kill the Little Sisters. For the sorta bad ending, you have to kill a few (then realise what you're doing) then save a few. It plays the same bad ending video but the overtone is a little more saddened rather than outright anger of the actual bad ending. I've started again on Hard mode now and I've just reached Arcadia...Big Daddies have reinvested the fear factor in me when going to fight them coz they take flippin' forever to battle with! :blink: That and your EVE consumption is worrying coz it takes SO much for just a single Electro Bolt!
On that note of plasmids and tonics, what do you tend to go into battle with? For plasmids, I tend to use Electro Bolt, Incinerate, Sonic Boom and Telekinesis (and what ever fills the last slot, normally Winter Blast). For the Tonics, I tend to use whatever helps along the healing process and the invisibility tonic (excellent for sneaking about and hiding if you trip the alarm). For defensive I use Electric Flesh so you shock the enemy if they decide to get too close...saves having to use the plasmid thus saving on EVE.