Korg PA3X, with two Bose Compacts. It does what it took two keyboards, several modules, mixers, compressor/limiter, equalizer, effects units, vocal harmony unit, numerous pedals, laptop (or stack of books with cheat sheets) etc., to do "in the old days". Not to mention huge speakers, sub, stands, and dollies, leslies, pedal boards, etc., depending on the other gear.
Nostalgia is nice, but who wants to haul around tons of gear these days, when it isn't necessary.
PSR S950 is second, because of new sounds, weight, great speakers and many of the above-mentioned items.
If there were a more ideal setup for me, I'd probably have it.
DonM