Charm+Bead+Biscuit+2 wards+ HP pot (wait in base for ~10 seconds after minion spawn for the pot)
Philo + Flask
Sightstone, Emblem of Valor, and Boots (been going Emblem first most often)
Boots 2 (Mobility, Tabi, or Mercs)
Crucible (take before SV if facing heavy cc like WW's suppresion or Amumu's ult, for example)
Upgrade Aegis to Bulwark at some point in there if AoE magic damage is an issue (or there's just a really fed ap carry). Also, tried getting an Iron Solari Locket before Crucible in a game where AoE was being a big problem in general (won the game, but not sure if this is optimal).
Has anyone else done any experimenting?