I would say anything designed by John M Browning. I'm fortunate to have a selection, mostly inherited over the years, so every time I walk into the Sin Cellar and pick one out it's like walking with an old friend or relative.
Model 12s, 1897s, my old Belgian made Browning Auto 5 is my go to waterfowl gun, the Winchester Model 24s (gold engraved and restored by Turnbull) my LC Smith 16 ga double, etc., are my upland bird guns.. all belonged to someone very close to me, all have their own memories...