Not necessarily a good idea...but...

Put the rear axle on some chinsey jack stands with the rear tires barely off the ground...or even just one tire, fire it up with it in a forward gear with the clutch pedal in, and have an assistant push the car off the stands. and as mentioned, if it brakes free and your foot is on the gas, its gonna rev fast. Be prepared. WHatever you do, don't take your foot off that clutch pedal.

That would be an absolute last resort, and as in the other methods mentioned... make sure you are in a safe place with nothing in front of the car, make sure the falling jackstand ain't gonna foul anything under the car (including brake and fuel lines) or your assistant, and make sure the car can ONLY fall forward.. that is, back it up to a tree or something.

And make sure you got your hand ready to shut the motor off instantly in case it don't break free. You'll basically need 3 feet for the pedals, two hands for the steering wheel, one hand to turn off the key. That adds up to 3 of each.

I don't recommend that method (or about any other for that matter) No liability will be assumed :-)

Good luck with it! Use your head, and be careful whatever you do!!!
-Matt