Here's a physics paper that analyzes that question. It's a joke paper, but the conclusion is valid (subject to various simplifying assumptions). Their conclus

Here's a physics paper that analyzes that question. It's a joke paper, but the conclusion is valid (subject to various simplifying assumptions). Their conclusion is that if a computation takes over 30 months to complete, you're better off waiting for faster hardware. http://arxiv.org/abs/astro-ph/9912202 http://arxiv.org/abs/astro-ph/9912202 The Effects of Moore's Law and Slacking on Large Computations Authors: C Gottbrath, J Bailin, C Meakin, T Thompson, J.J. Charfman We show that, in the context of Moore's Law, overall productivity can be increased for large enough computations by `slacking' or waiting for some period of time before purchasing a computer and beginning the calculation.