When telemarketers harass telecoms companies

farnz writes: "Andrews & Arnold, a small telecoms company in the UK have recently been hit with an outbreak of illegal junk calls. Unlike larger firms, they've come up with an innovative response — assign 4 million numbers to play recordings to the telemarketers, put them on the UK's Do-Not-Call list and see what happens. Thus far, the record is over 3 minutes before a telemarketer works out what's going on.

What ideas have Slashdotters used to keep telemarketers at bay?"