From Native Instruments:
Kontakt Player is a free, expandable software instrument that can be used both standalone and as a plugin in any popular music sequencer. It is based on the powerful Kontakt software sampler that has become a standard with professional musicians, producers, and composers.
To get started with free sound content, users can download a complimentary "Kontakt Factory Selection" with 50 studio-quality instrument patches from the Native Instruments website at http://www.native-instruments.com/en/products/producer/kontakt-player/free-download/
Kontakt Player can also be expanded with a wide range of affordable download packs that accommodate various musical styles and genres - ranging form authentically emulated grand pianos, electric piano, acoustic bass, strings and drums to cinematic soundscapes and special effects for game and movie scores.
The Kontakt Player also doubles as a time-limited demo of the full-featured Kontakt 4 sampler, allowing users to play any of the many available professional sound collections in Kontakt format for 15 minutes at a time.
What's new in this version:
Version 4.1.1 improves the general reliability and performance of the software.