In my post on PowerShell Objects - http://richardsiddaway.spaces.live.com/blog/cns!43CFA46A74CF3E96!1875.entry - I mentioned Tee-Object and gave an example. Mats left me a message asking why Tee and asking did it mean temporary.
I had always looked at it as a branching - much like a T join in pipes. The help file says "The Tee-Object cmdlet send the output of a command in two directions (like the letter T). "
Think of it as a dead end branch off the pipeline.
Read the complete post at http://richardsiddaway.spaces.live.com/Blog/cns!43CFA46A74CF3E96!1888.entry