I've tried the following methods (ordered from slowest to fastest):
* Turtle Wax's Bug and Tar Remover
* Lighter Fluid
* Hand Sanitizer Gel
* Alcohol
* Peanut Butter
* Clay Bar

The clear winner by an order of magnitude above all else:
Magic Eraser used with something like Meguiar's Quik Detailer. Use it like a clay bar but with MUCH LESS pressure. Gently rub it and those stubborn suckers come off like magic.

It's micro abrasive, so it's probably leaving micro scratches in the clear coat, but I'm willing to trade the HUGE time savings for this.

Finish it off with wax or sealer.

 

What about goo gone or goof off?

 

Never tried that. Did it work for you?

 

"CitraSolv Natural Cleaner & Degreaser" works everytime on virtually anything.

 

warm olive oil works wonders, if i'm in a hurry i just use acetone and then wash it.

 

http://www.autogeek.net/tarminator.html give this a shot, I have heard great thinks about it over on the autogeek forums.

 

Goo Gone (which is citrus based)

or wetted newspaper left applied overnight.

 

Clay Bar FTW. I would never let anything thats a solvent or abrasive anywhere near my clear-coat. The difference is worth it in the long run, my factory paint gets compliments to this day...6 years after rolling outta the factory!

 

Big time no on the claybar. If there is any **** inside the sap it is going to have a field day scratching your paint as you try to clay it off. Spend 6 bucks on a good tar/sap remover like the one I linked, which is non abrasive, and call it a day.