Storage Engines in Data Bases

Mongodebe is probably somewhat famous for having several search engines, or at least, you know, they migrated from one to another. Some storage engines are targeting themselves as a component that can be simply dropped in some data basem. I hope that the trent genious and more folks actually try and make their store tentions plugable and start using them off the shelf. Weell ready to use solutions. Maybe roxte b arnwire tiger to be the best contender, so to say.