Me calling some help place- even if they are the biggest bunch of morons going I will stay my tongue, I am still proud of the time I crashed a guys machine when he send me a remote access app (I had four screens at highest res+ crappy UK upload speeds made even worse as that was one of the things I was calling about- despite being told several times I did not use IE, it applied to all machines and operating systems including live CDs he proceeded to launch it and clear my cache and cookies).
Usually calling such a place is a token effort along the lines of "yes I called your people, send me a new one".
Those calling me, I agree it is a horrible job so I avoid making it personal. I seem to recall the margins on these places are about as tight as internet gambling sites so I figure if I can do my part to drag profitability down. I have also long been affiliated with elderly care types and similar trades and I have a very long list of horror stories from that side of things.
Most people in this house have several names (in addition to aliases) so you can usually weed out the good ones right away (the bad ones will use the long form/formal name or an alias).
Surveys- same story as street level surveys with wrong info and bad info (12 people in the house, 14 kids sort of thing) along with counter intuitive answers (I will take the holiday but keep the money) and after that it is usually either:
legal- Ambulance chasing is not something that sits with me so given that I can spin a story for injury claims all day long and usually back it with a fair level of medical knowledge (injury claims are so similar to all the various things I and others can fall off of or otherwise be hurt from), such calls tend to end with "I am not sure I want to go forward/why would I want to go forward.
gas and electricity people- I use gas bottles and fuel cells apparently.
credit companies- one of two types I find, the first is a fishing expedition so I am a boss of a company or otherwise a highly paid type (the big fish approach) and the second is a more targeted one in which case "I only just got this number but your offer intrigues me" or I am the second person in the household.... return to "big fish" approach. A nice side effect of the big fish approach is they will usually have to get a supervisor which is a great point to ditch a call.
mobile phone companies- I lack a mobile phone and could not be happier about the situation, alas I know so little about mobile phones I can not spin stories so I will usually hang up early here.
If I get especially bored I will put them on "hold" (play some music from my computer, I have not broken that 8 minutes record mentioned earlier though but I guess whatever rock/metal album I have open is not good "hold" music.
Other times I will hang up halfway through a sentence (they usually call back) and pass the phone to one of the others in the house for "I have only just got in and I am the only one here, I have no idea who you were talking to" or if nobody is around I might disguise my voice or just carry on with normal voice and flat denial.
Alas I seem to have done this for so long I tend to only get machines calling me, most are set up well now but I still get a few that will tie up lines if you leave them without pressing buttons (a hangover from rotary/pulse telephones).
Door to door types- rare around here and as I usually wear headphones sitting upstairs and can see the front door from the front room if not I do not interact with them.
Street level- they never seem to bother me and I do not feel bad about not taking their leaflets, should they block I sidestep or remove them from my path.