If you're into the shabby-chic look, and you want to age/weather wood faster than you've got time for. all you need is access to a sand-blaster.
Step 1: Take a Fresh Cut piece of wood and Put it in the sandblaster
Woods with high contrast grain usually have a hard grain and a soft grain. This piece of pine has a vertical grain. All you have to do is aim the sandblasting gun at the wood. The longer you do it the more soft grain will be removed and the more textured it will become
Step 2: Brand new weathered wood in 10 minutes