Gralian said:
Animal Friend perk in Fallout 3.
Seriously... why?
I took both levels of that perk. It was nice to not have Yao Guais attack you, and it could also prove useful when a friendly pack of vicious dogs draws your enemie's gunfire from you.
I'd say the Bloody Mess perks in the Fallout games. It was purely aesthetic, and had no real affect on gameplay. (Well, there was the +5% damage done in F3, but come on...)
Also the karma altering perks (Devil's Highway, Karmic Rebalance, Escalator to Heaven), as you can easily alter your karma in ways that don't really affect the game, without wasting a perk.
[spoiler: Level 30 perk.]And finally the Nuclear Anomaly perk, which makes you explode like a nuke when your health drops below 20. The fact that this also damages companions makes it a pain if you choose to have them, and also it's heavily outweighed by the other level 30 perk, Almost Perfect, which raises all your S.P.E.C.I.A.L. skills to 9. I don't understand why anyone would choose the former perk over the latter.[/spoiler]