I get all the usual calls, the ones from "Microsoft" I say, "windows, there's nothing wrong with my windows, I can see out of them quite clearly"
or else I say "ooh Microsoft, great my husband is CEO of the company, can you put him on please".
One lady I put the phone by the speaker and played her Radio 2 for a while, she seemed to like it as she kept talking.
The other day I had one ring me about my gas. So I asked him if he was going to supply me with gas and how he was going to get it into my house as there is no gas supply here.
If they claim to be calling about my BT broadband, I say but Im not with BT I'm with EE (not real company) and then they say, oh yes but I am calling from EE!
One caller said he was calling about problems with my computer, so I said "ooh, do you want my credit card details, how about the PIN number"? He replied, "no I want to fk you, I want to your pussy". Best offer I had had in a while, but I turned him down
.
The last one I had, said he was calling about my phone line, so I told him that I didn't have a phone. He apologised for bothering me and hung up 
I only ever do this with the genuine scam calls, not the sales calls, although they are annoying, they are actually doing a job, not trying to scam. Sales calls I just say Not Interested Thanks and hang up.