Tone2 UltraSpace 

Download the demo now for free from tone2.com
UltraSpace is the complete ambience-modeling solution. It can simulate nearly any kind of room, echo or acoustic environment with high-end sound quality.
UltraSpace is far more than just another reverb - it's a complete compilation of different effect units covering all important aspects of space simulation. By combining these units, completely new and unique effects can be created.