If I worked your job I would be messing with people like that too. If you do try it let us know how it goes. Hopefully you dont get yelled at.
The funnest part I had, was when I phoned this lady for collections (she owed about 3 months worth of bills for her cell phone). I'd asked for some time frame ie tomorrow, or next week, etc. (she'd said soon), and she flipped. After her going off for about 5 minutes or so, I'd asked her if she was done yet, and she said she wasn't, so I said "by all means, please continue" and she went off again for another 5 minutes or so. She slammed down the phone when I wished her a nice day (in the politest voice possible). I'd just put my feet up and tuned her out, and didn't let her get to me. My co-workers and I laughed about that for a while after wards. She also gave me her visa to take an immediate payment.
That, or the call when some young lady called about her bill... to find that it was at $24,000. This was back around 2003, and LD rates between the Northwest Territories and Lebanon were a little bit higher than they are now. She called in and asked for her balance, and was like, okay thanks, like she didn't have a problem in the world. She sounded very young (18-22 maybe?). It took a few years, but she eventually paid it all off.
I supposed I would do that too if I was in a crappy job like that. Well, if they are paying you enough, then I guess it would be tolerable.
It was a small call center. At it's peak it had 6 call center reps. When things slowed down, there were 4 of us. We all got along very well, and had a ton of fun. And they paid very well (thanks union).
But I don't do that any more, I'm in the technical side now, so if a customer is a complete ass to me, I just hang up, and put their ticket off for a few days... But now, as I'm fixing their problems, they're almost always very pleasant to deal with.