I like the White Herb + Superpower/Overheat idea, and I just tested it with my Regirock. It works, but white Herb only worked once...
Hmm... now I lost White Herb... OMG don't tell me it's a one-use item!!! Where do you get more? ...
Anyway, I've been told that Speed Boost + Baton Pass doesn't work. It only works for Ninjask.
Own Tempo + Berserk Gene, although I haven't tried it, should definitely work.
The Soundproof + Mean Look + Perish Song combo sounds great... but only a few unobtainables can actually make use of it. A combination of pokemon should make this effective.
A Gengar or Jynx with Mean Look + Perish Song + Skill Swap can swap the soundproof characteristic of Mr. Mime/Voltorb/Electrode/Whismur/Loudred/Exploud.
This works well in 2v2, too. But if you skill swap your soundproof partner and use Perish Song, it will die if you use Perish Song... so, after skill swapping, switch the once-soundproof partner to... something else.
Or better yet, don't use Skill Swap. Have one soundproof partner and a perish song user. Use perish song, switch the perish song user to a mean looker, and then trap the two other pokemon so they can't switch. The soundproof partner and the newly switched pokemon are not affected by Perish Song.
It requires some Baton Passing (BP) in 1v1, though.
Have Ariados/Umbreon use Spider Web/Mean Look, then BP to Absol/Celebi, which uses Perish Song, and then BP to Electrode/Exploud/Mr. Mime (Soundproof).
Problem: Only unobtainables can trap and BP... I think. Umbreon and Ariados.