Interesting approach, leveraging file attributes combined with fast file searching:
SkyOS Application (De)Installation Technique Explained
Looks like SkyOS (videos and nice wallpapers) is pretty innovative in other fields as well. For example, I like the fact that its Live-Query application doesn’t hide the query language from its users. It would be nice if Google and co. were esteeming and supporting power users too (I’m still waiting for a search engine that offers a public regexp interface).