Bigcat Instruments has released MSLP Project, a free library collection for Kontakt by Native instruments featuring MSLP instrument library by Erick Kvist (Creative Commons instruments of widely variable quality).
A flute with over 900 samples, 180 megs compressed. There are vibrato and non-vibrato modes with 3 velocity layers, round robin staccatos and more.
A trombone with 650 samples, 84 megs, 3 velocity layers, staccato round robins, gliss, swells and more.
A cello weighing in at 68 megs with 800+ samples and 3 velocity layers in sustain and staccato and more.
The fully sampled Piano Grand Soft it has one soft velocity layer so it works nicely as an intimate piano.
And for some of your assorted Idiophone needs (we all have them). A Marimba and Xylophone that are fully sampled with two velocity layers and mute layers and a Vibrophone with only 1 velocity layer but long, short, mute and bowed samples.
Strum Acoustic and Electric guitars.
There is also a collection of sampled toys including a fun noisy 3 layer toy piano, a melodica and a funky hippo harmonica.
Also audio toys of less quality including lots of basses a fiddle and a banjo.
MSLP Project Kontakt library is available at no cost.