Alpha V2 425 10.5* -- even at 44" last year, I hit a couple 280, which is really long for me. It was summer, and the fairways were dry, but that's 40 yards longer than I expect nowadays.
SMT Indio with a Harrison Striper -- I couldn't draw that club to save my life, but when I reared back and allowed for a 40 yard slice, it was as long as anything. But if there were trees down the left side, I had no chance.
I have a few 47-48" drivers now that get me another 15-20 yards, but none are longer than the others. Adams 9015D with an old Aldila Longwood, one of Cutter's Fisters with a Matrix Black Tie, an E-Power 420 with an Accuflex LD.