BSP tutorials needed

Can anyone recommend any good tutorial on BSP(PVS)? PLEASEEE…

BSPs (based on nodes or on leaves), Portals and so on, are preprocessed space partitioning algorithm.
“BSP” aims at building a binary tree by subdivising the space by planes liying on polygons. So, you can easily get polygons sorted (thus, no problem of transparent polygon) with specific graph traversal. But the performance strictly depends on the database complexity.
“Portal” divides the space in rooms and portals (used for indoor databases like quake…), so there will have no overdraw (only visible rooms will be rendered) .
Here you can found some links:

If you want more links, write to me
Or make a search using the “BSP” word and you will get a lot of links !

Thanks Sancho, you helped me much, but I have one more question: Ive heared that its easy to do collision detection when using BSP. Is it realy so?

P.S. Thanks one more time.