Taylor Sampled Synths for Kontakt
Bender Roma Equator
King 1 Many Part 1 Part 2
Newtron V Part 1 Part 2
Richard Taylor did a great job sampling analog synths and the nice folks at Freesound.org are hosting them. They were placed in the public domain which was very generous of Richard Taylor.
I'm calling the first one Axis 80 so as not to get sued, read about the real thing here. It has over 30 presets and weighs in at a touch under 2 gigs.
The King One Many is a classic synth from the early 80s. Check Wiki for the real deal. This one is more 1.5 gigs, 3000 samples and 50 presets.
The Newtron 5 is an interesting modern synthesizer. This almost 2 gig download
has 19 presets including interesting arps and sounds that seemed designed to stack in interesting ways.
I used Mickaël Ménager's great script and GUI, so you can add effects like Tremolo, Phaser, Reverb and Distortion along with using half a dozen amps.
As a bonus:
AKWF The First Attempt
Adventure Kid is Kristoffer Ekstrand and he has sampled many wave forms and placed them in the public domain because he is cool like that.
As with the previous synths, the script and shell are by Mickaël Ménager.