A couple more:

Gerald Dey - for good quality freebies
x2000 - for really cool space freebies
Morris, Vali and Gwendelyn - for stunning textures and characters
Pretty3D - for making V3 ultrasexy! also, great clothing!

@Masha, for those you've already listed:

As Shanim - at least for his(?) cool Gothic Dungeons and the MyShirts
Nerd3d - for the V3 walk designer addons
BVH - for some killer outfits and his tutorials on putting poser characters into MSAgent

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AMD FX-9590 4.7ghz 8-core, 32gb of RAM, Win7 64bit, nVidia GeForce GTX 760

PoserPro2012, Photoshop CS4 and Magix Music Maker

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...and when the day is dawning...I have to say goodbye...a last look back into...your broken eyes.