Any way to...

[The Dong]

Make use of this with basic service?:

http://www.phonespamfilter.co.uk/

I reckon BT (or whoever you rent your line from) should offer this 
integration into my/your line, for free of course. But I wonder if there 
isn't an easy way to set up a tiny pabx to kill all numbers high on the 
list? They mention Asterisk (*) on Linux, anyone with experience?

I get at least 2-3 cold calls a week and while that may not sound like 
much of a hassle, it is beyond a joke having to repeatedly tell them not 
to call this number when they know well enough already a law is being 
broken by doing so.

All hunting for your information, because even acknowledging your name 
to them is worth something. Don't! :)