[Herts] black hole emails

[Tony Friis]

Hi all

Does anyone know how to send an email to oblivion?
I have an ISP who lets me use any number of emails in front of my domain 
name, such as this at friis.co.uk that at friis.co.uk or theother at friis.co.uk 
one or two of these (say that at friis.co.uk) now collect so much spam I 
just want to throw them all away. At present I use an email rule in 
Thunderbird to send them straight to trash, but I still have to empty 
them from the trash.

My ISP lets me redirect any particular address like that at friis.co.uk 
wherever I want, I was hoping to redirect it to somewhere like - perhaps

     blackhole at null.com

but I don't know if there is any such email address?

Has anyone heard of such an address, or any other ideas

Tony