Two-tone Green GPO 746...

[GG]

We recycle numbers in the US too.  One of my numbers formerly belonged to a Bill Gates (not the same one, but none the less).  After a few instances of people calling to speak with him, I'd start saying "I'm sorry but Bill moved up to Washington to run a software company.  You may have heard of it, it's called Microsoft."  The calls gradually stopped.

In college we had a number that was one digit off the local drug store, so we would get calls "Is this So-And-So's Drugs?"   After a while we started replying, "Yes, and this week we're having a special on LSD, but kids under 16 need a note from their parents."  Yes there were people who believed this was serious, and we had to tell them, "It's a joke, and the real number for So-And-So's Drugs is NXX-XXXX." 

To make telemarketers go away: try either of the following:

Ask them if you can pay for whatever-it-is with your welfare check.

Tell them they've reached Edna's Escorts & Hourly Motel, and ask if they'd like to book a room for a very special date.

Etc.