I know you were speaking ironically, but I've hired goats for old-field recovery (rehabbing a field site that infilled with exotic shrubs like english/eurasian privet, honeysuckles, multiflora rose, buckthorn, russian and autumn olive).
They bring in the goats, stake them with a 15-20' chain and let them eat to their heart's content. You're paying for transportation to the site, veterinary care, water, and supplemental feed (the food quality is so bad, the goats can starve to death packed full of roughage).
We did a chunk of land like this, and a chunk of land with volunteers with swedish axes, saws, and loppers. The goats did a more thorough job and MUCH faster (and you didn't have to burn a brush pile after). The only downside to the goats is they're non-selective... you can't leave any nice native species you find (bye bye hazelnut!).