My warranty is up in the middle of next month, so I decided to spring for Applecare if I could get it cheap enough. I already had a commitment from the manager of an Apple Store that I could purchase it there for the 'educational' discount ($239) because I had asked about it, and mentioned that it was available online in many places for a lot less than the $349 that the Apple store was selling it for. At first they didn't believe me (or so they said) until I pulled up some third-party prices on Amazon, etc. So, the manager offered me a discount, which I asked him to write down on his card so I could use it later.
Short story long... as they say

I decide to check out the ebay scene, and saw it selling for various prices, from $245 to $175 and $169 and $159 (all listed as "buy it now" prices) and various auction sales where winning bids were in the $160-180 range. I figured I'd pull the trigger on a $159.95 Buy it now! deal and use paypal for the protection usually offered. I checked the sellers rep/rating out (99.8%) and looked at some of the customer feedback. All of the feedback was positive and for Applecare purchases, indicating almost instant delivery and success registering the products with Apple. But, I noticed that for some buyers the prices varied, down to even $130 for the same product for Macbook Pros.
Not seeing a place to bid anything other than the "buy it now" price of $159.95, I checked the sellers other products, and noticed the same Applecare listed at $169.95... with one difference. While still having that as a "buy it now" price, there was an additional button on the higher priced product which said "Buy this product for less. Make an offer." So, the old lightbulb went off, and I realized how some folks were getting it for less than others.
I clicked the "make an offer" button, and typed $130. Within three seconds I was informed that my offer was accepted. I was a bit shocked, and then slapped myself for not typing in $100, or $105, or whatever until it was actually accepted to see how low I could go. Obviously they had already put in a minimum price which if you met or beat, you got the deal.... so I don't know how low you might actually be able to buy Applecare for.
End of story. Within an hour I had my registration code and instructions emailed to me. I enrolled the Applecare plan at Apple support, and by the next morning I had my Applecare Protection Plan Proof of Coverage issued by Apple.
Word to the wise... keep copies (web receipts) of your purchase and also your original receipt for your computer purchase - just in case they're ever asked for. It doesn't matter what you pay, just that you did buy them legally.