Pretty vague question, but here is my vote/s. Let me first state that I am in fact a 12 gauge, semi-auto chauvinist.

Overall: Browning Auto-5 Magnum 12. Belgium or Japan I don't care, same gun.

Waterfowl: Browning Gold 3 1/2 12 ga. with 28" barrel in shadow grass.

Upland: Franchi AL-48 12 ga. with 26" barrel.

Turkey: Browning Gold 3 1/2" or Benelli SBE with 24" barrels and camo.

Crow/Early Waterfowl: Beretta Pintail (ES100), Franchi 612, or Weatherby SAS. All in 3" 12 ga. with 26" barrels and camo.