I have worked with and used Rustoleum products for many years.  This is a sponsored post and all opinions expressed are my own.

A couple months back in a video episode, we turned a leftover pile of 1x6 tongue and groove into a backdrop for our staircase -

I was really hoping for lots of gray aged boards, but we only ended up with a few.  Varathane recently debuted a product called Weathered Wood Accelerator, that ages wood in minutes