All of these examples have been said - I have heard them!

Example 1: "I don't know, let me ask my supervisor."
This gives the customer the impression that there is someone here that knows more than you. In the customer's eyes, you know it all. If you are uncertain, say instead "Please hold a moment while I research this issue for you." Moreover, the word "supervisor" should not ever be said to a customer. Again, it gives the impression that you are not the ultimate authority with regard to your product. Please try to limit your calls to the Internal Support Line to twice per call, putting the customer on hold 6 or 7 times to ask the mentor a question will make the customer wonder what you are doing. Please try to figure it out on your own first and learn how to use your online resources - about 50% of the calls I receive could have been avoided if the technician had used the online help.

Example 2: "Well, this shows up on the Virtual Whiteboard, so I can't OTE this, they say we need to script this call."
"Internalisms" like this mean nothing to the customer. We don't want to say anything like NHD, NHI, OTE, ESS, scripting calls, virtual whiteboard, Tier 1/2/3, and we certainly do not want the customers to know what our handle time is or how many people are holding. Just tell the customer what he needs to know. "I am seeing that there is an issue in your area. Please let me gather some information so that we may continue to track it and have you up and running as soon as possible." When transferring, use the terms "customer service" "a specialist" or "the next level of support."

Example 3: (call the Internal Support Line) "This customer is a total idiot! He isn't doing a single thing that I am saying! Transfer this call up please because I have been on it for 40 (expletive) minutes. This customer is driving me crazy, he is such a (expletive)!
Your calls can be, and often are, recorded. That part is recorded as well. Do not use the mentor to vent about your caller until you are far away from the phone. I will listen all day to what you have to say about it, but not over a medium that is not confidential by any means. Also, we cannot transfer calls simply because it is hurting your call time, we have to follow procedure as much as you do. We do not enjoy sending you back to the caller to complete troubleshooting steps that you have not done, we have to do it in order to verify that we have done all we can do in this issue and that it is definitely something that we are allowed to transfer.

Example 4: "Little elves crawl into your house at night and chew on your Ethernet cable, that is why you have intermittent connectivity."
Sarcasm - just do not use it. It is not professional at all, and while it is important to establish rapport with the customer, and humor can be ok from time to time, sarcasm is not. It is easily misunderstood over the telephone as rudeness.

Example 5: "That is out of our support boundaries."
Customers take this one of two ways: 1. They don't get it, or 2. They see it as "I don't want to help you." For some reason that phrase does not sit well with the end-user. The best thing to say about that is that we are not certified to support that product, and we could be held liable if we do.

When followed correctly, this will make you sound like a very professional tech support provider that customers love to talk to, and that I do not have to come around to your cubicle and kick your butt for being dumb.


Update!!!
I love all the things that you have added, and I have a couple more for you:

"We have 200 calls holding, you should be able to do this yourself." This is not what they called tech support to hear. Get over it and solve the problem. Clearing the queue is not your issue, fixing your customers is the issue.

"I don't think it's a good idea for you to speak to billing at this time." If the customer asks to be transferred to another department or to a supervisor and you have the capability, do it. Usually it means they just don't want to talk to you anymore anyway and if you fight with them, they will only be more irate toward the next person that they talk to.

"You're a web developer huh? Well, I do a little HTML myself. I learned all my HTML on Notepad. Do you know what Notepad is?" Ack, why don't they fire these people? At least the customer could play along in this case. "No sir, I have never heard of that program before in my life." Why why why do I do this? I'm not a slavedriver, as someone so lovingly soft-linked, I just don't want people to be stupid. There are so many stupid people in the world. The last three examples were actually from the same technician.