Due to the rash of shipping rapeages going on, I figured I'd let everyone know what I typically do in a rape situation:

Pay for the auction itself via Paypal, then pay for the shipping charges separately via Paypal. Send the money as "goods" and put a description like "ebay item xxxxxxx" in.

Many auctioners will yell and scream about extra Paypal fees, but the fact of the matter is you do NOT have to use the eBay/Paypal checkout system for an auction.
If the seller goes way overboard with the charges, break the payments up into $1 or $10 increments, or even 10 cents. Again, there is no rule saying the money has to be paid in one lump sum.
Mean and nasty? Yeppers. Do I give a rat's ass? Noppers. I haven't had to do this often, but when I have had to, it has proven quite effective.
Obviously, if people refuse to combine shipping, pay for one item. When you receive it, pay for the next. Etc. etc.