With all those newfangled Economy 3.1 jobs attracting rich rubes from the hinterlands, there's soon to be be a great increase in the need for Manhattan butlers, reports today's Post. And yes, they make much more money than you do. How much? If you're "well-groomed" (and, one presumes, clean and articulate), expect $200,000 a year, plus a 401(K) and, of course, free housing. Acquire a British accent, and that figure jumps by $10 to $20K. So, all you Ivy Leagued publishing drones and M.F.A.'d copy editors out there, hold off on those enticing subway trade-school ads: The Dutch-based International Butler Academy is planning to open a New York branch soon.